What is called steel

What is the difference between steel and metal?

Ferrous metallurgy products are widely used in many sectors of the national economy, and ferrous metal is always in demand in construction and mechanical engineering. Metallurgy has been successfully developing for a long time, thanks to its high technical potential. Cast iron and steel products are most often used in production and in everyday life.

Cast iron and steel both belong to the group of ferrous metals; these materials are alloys of iron and carbon that are unique in their properties. What are the differences between steel and cast iron, their main properties and characteristics?

Steel and its main characteristics

Steel is a deformed alloy of iron with carbon , which is always up to a maximum of 2%, as well as other elements.

Carbon is an important component because it gives strength to iron alloys, as well as hardness, thereby reducing softness and ductility.

Alloying elements are often added to the alloy, which ultimately results in alloyed and high-alloy steel, when the composition contains at least 45% iron and no more than 2% carbon, the remaining 53% being additives.

Steel is the most important material in many industries; it is used in construction, and as the technical and economic level of the country grows, the scale of steel production also increases. In ancient times, craftsmen used crucible melting to produce cast steel, and this process was low-productivity and labor-intensive, but the steel was of high quality.

Over time, the processes for producing steel changed; the crucible method was replaced by the Bessemer and open-hearth methods of producing steel, which made it possible to establish mass production of cast steel. Then they began to smelt steel in electric furnaces, after which the oxygen-converter process was introduced, which made it possible to obtain especially pure metal. Depending on the number and types of connecting components, steel can be:

• Low alloy
• Medium alloyed
• High alloy

Depending on the carbon content, it is:

• Low carbon
• Medium carbon
• High carbon.

The composition of the metal often includes non-metallic compounds - oxides, phosphides, sulfides; their content differs depending on the quality of the steel; there is a certain classification of quality.

The density of steel is 7700-7900 kg/m3 , and the general characteristics of steel consist of such indicators as strength, hardness, wear resistance and suitability for various types of processing.

Compared to cast iron, steel has greater ductility, strength and hardness.

Due to its ductility, it is easy to process; steel has a higher thermal conductivity, and its quality is improved by hardening.

Elements such as nickel, chromium and molybdenum are alloying components, each of which gives steel its own characteristics. Thanks to chromium, steel becomes stronger and harder, and its wear resistance increases. Nickel also imparts strength, as well as toughness and hardness, and increases its anti-corrosion properties and hardenability. Silicon reduces viscosity, and manganese improves weldability and hardening properties.

All existing types of steel have a melting point from 1450 to 1520°C and are strong, wear-resistant and deformation-resistant metal alloys.

Cast iron and its main characteristics

The basis for the production of cast iron is also iron and carbon, but unlike steel, it contains more carbon, as well as other impurities in the form of alloying metals. It is fragile and breaks without visible deformation. Carbon here acts as graphite or cementite and, due to the content of other elements, cast iron is divided into the following varieties:

• White - where cementite is in the lead in the majority, this material is white at the fracture. This component is fragile and at the same time hard. It is easy to work, which imparts malleability to cast iron.
• Gray - in this variety, a large proportion is graphite, due to which the cast iron is ductile. Ready cast iron has a low melting point, is soft, and is easier to cut.
• Malleable - achieved by firing white cast iron, it is simmered in special heating furnaces at a temperature of 950-1000 ° C. The inherent hardness and brittleness of white cast iron are reduced; it is not forged, but only becomes more ductile.
• High-strength cast iron alloy - it contains nodular graphite, which is formed during crystallization.

The melting point of cast iron depends on the carbon content in it; the more of it there is in the alloy, the lower the temperature, and also its fluidity when heated increases. This makes the metal non-plastic, fluid, and also brittle and difficult to process. Its melting point ranges from 1160 to 1250°C .

Cast iron has higher anti-corrosion properties because it undergoes dry rust during use, this is called chemical corrosion. Wet corrosion also attacks cast iron more slowly than steel. These qualities led to a discovery in metallurgy - steel with a high chromium content began to be smelted. This is where stainless steel came from.

We draw a conclusion

Based on their numerous characteristics, we can say the following about cast iron and steel, what is their difference:

• Steel is stronger and harder than cast iron.
• Steel has a higher melting point and is heavier.
• The lower percentage of carbon in steel makes it easier to work with, easier to cut, forge and weld.
• For this reason, cast iron products can be cast, while steel products can be welded or forged.
• Steel products are less porous than cast iron, so they have greater thermal conductivity.
• They also differ in color: steel is light and shiny, while cast iron is darker with a matte surface.
• The cost of steel is always higher than cast iron materials.

We can conclude that steel and cast iron are united by the content of carbon and iron in them, but their characteristics are different and each of the alloys has its own characteristics.

• Nikolay Ivanovich Matveev

Source: https://varimtutru.com/chem-otlichaetsya-stal-ot-metalla/

Stop calling everything AI

Most managers and marketers call artificial intelligence everything: vacuum cleaners, toy transforming robots, and even the selection of mobile tariffs. It’s trending and selling well, there’s only one problem - even scientists don’t risk saying that they created AI. We decided to look into the definitions: can we even talk about artificial intelligence, how does it differ from machine learning, and is it fair to raise our eyebrows contemptuously when we see another advertisement with AI.

AI for Wikipedia

The definition of artificial intelligence from Wikipedia is abstract and universal, like a horoscope. Artificial intelligence is the science and technology of creating intelligent machines, especially intelligent computer programs. This formulation does not say anything, because it is unclear what is considered “intelligent” in the world of machines.

On Wikipedia they write about intelligence as a quality of the psyche, and only living beings possess this thing.

Intelligence (from lat.

intellectus "perception"; " understanding ", "understanding"; "concept", " reason ") or mind - a quality of the psyche consisting of the ability to adapt to new situations, the ability to learn and remember from experience, understand and apply abstract concepts, and use one's knowledge to control the environment around a person.

Therefore, in search of an adequate definition, we went to the websites of laboratories and institutes studying artificial intelligence.

AI for scientists

Globally, the topic of AI is not an easy one, because even among experts there is still no generally accepted definition - everyone understands artificial intelligence in their own way.

Therefore, we decided to look at what laboratories and departments that are engaged in AI research are studying: Moscow Institute of Physics and Technology, Center for Speech Technologies at ITMO, ISA RAS, laboratories in companies and corporations (for example, Sberbank, Samsung, VKontakte) and other institutions.

For example, their areas of study include:

1) Predictive analytics - intelligent data analysis, based on which algorithms can make a forecast. For example, when Sberbank makes a decision to issue a loan, their Big Five technology analyzes the client’s social networks, compiles a psychological portrait and assesses his trustworthiness.

2) Recommender systems are algorithms that select objects for the user: content, products and offers. We are all familiar with this: if in a moment of drunken sadness you put on “I’ll go out into the field with a horse at night,” the hosting will remember you as a fan of “Lube” and offer to listen to the battalion commander’s father.

3) Computer vision and image recognition is a field of AI that teaches computers to interpret and “understand” the visual world. It is used, for example, in self-driving cars or in services like FindClone, which finds people on VKontakte using a photo.

4) Speech synthesis, recognition and generation - what Siri, Alice and other virtual assistants can do (we wrote more about the work of such algorithms and our Lia in a previous article).

We see that the term artificial intelligence is used in tasks where the system analyzes data and makes “smart” decisions based on this. But not a single researcher says that he created AI - institutes only study algorithms that perform tasks in the field of AI.

AI and machine learning

AI is often confused with machine learning, but this is incorrect. ML is often used for these tasks because it is convenient to analyze information and make decisions.

For example, the ML algorithm will predict that with 98% probability the person in the picture is a smartphone user. This means the phone can be unlocked. But scientists do not equate ML with AI.

For them, artificial intelligence is an area of ​​research about how to make a machine perform non-trivial tasks. And ML is a class of algorithms that serve to solve them (like cogs in a watch).

AI for snobs

Those who like to get to the bottom of things say: “This vacuum cleaner is not smart because it can’t cook lasagne or argue about Kant. AI should be like an oracle, ready to answer any question and solve any problem.” This idealistic image of a machine as a superman came to us from cinema and art. Romance AI is a smart robotic girl from the movie “Her” or “Terminator”, ready to sort out all the problems with one left hand.

This is not a chatbot that breaks at the first request outside the script. There is a special definition for what snobs mean by artificial intelligence: strong artificial intelligence or general artificial intelligence. A utopian algorithm that can cope with any task without prompting: the same hero capable of anything. Like a person, only infallible.

The theory of strong artificial intelligence suggests that computers can acquire the ability to think and be aware of themselves as individuals (in particular, to understand their own thoughts), although their thought processes will not necessarily be similar to those of humans.

Conventional or as it is called “weak” artificial intelligence differs from “strong” in that it is written for specific tasks: for example, in a drone, one algorithm analyzes the road, and another, based on this data, understands where to go. Yes, this is ML - and yes, from the field of AI. But unlike general artificial intelligence, it will not be able to act in conditions of uncertainty: raising children or saving the world.

Perhaps simple AI is called weak because it does not live up to human expectations. While there is no strong intelligence, we are left with only simple robots - they pretend well, but everyone who has communicated with chatbots or even Alice knows how easy it is to figure them out. Although marketers, of course, don’t talk about weaknesses.

AI for marketers

Managers and marketers call AI all smart devices and any smart crap that can do something on its own: drive around the apartment, turn on the lights, select goods. A recent example from the advertising world: MTS artificial intelligence will generate a personal tariff for you. AI here can be replaced with the words “algorithm” or “assistant” - for the user the essence will not change, it’s just a fancy word.

The banner, of course, doesn’t say what MTS has under the hood - maybe they have their own regular Terminator. But skeptical programmers immediately understand that this is most likely a simple implementation based on well-known algorithms. We expect that artificial intelligence will surprise us, and calling it clumsy methods is at the very least naive.

But marketers have never been humble (or even realistic).

How to do it right

Artificial intelligence has only just begun to be studied, so talking seriously about AI in advertising is like calling a schoolchild an “aspiring master’s student.”

Then which is correct? We think that at the moment, when talking about AI, it is best to use the definition “machine learning algorithms” or say that the technology is built on AI algorithms - an expert will give you a plus for this.

Potential users will also thank you: it’s unfair that managers put the big idea of ​​artificial intelligence on the same level as a “smart” vacuum cleaner.

After all, we are still far from real (strong) artificial intelligence.

Source: https://habr.com/ru/post/484716/

Properties of metals

To successfully create decorative products, you need to know the basic properties of the source material, as well as the technology for working with it.

Nowadays, both pure metals and their alloys can be used to make dishes, jewelry and various interior design items.

Artwork - silver vase

All metals and alloys created on their basis are divided into two large groups with different properties:

• Ferrous metals - steel
• Non-ferrous metals - copper, bronze, brass, zinc, tin, aluminum, lead and silver.

It is these types of metals that are most often used to make decorative items, dishes and much more. Therefore, let's look at their properties and features of metal processing.

Steel 

Steel belongs to ferrous metals. Carbon steel, which is an alloy of iron with carbon and other elements, is best suited for artistic processing. Steel has high quality characteristics, including the following:

• Elasticity
• Strength
• Hardening ability - a piece of steel is heated at a high temperature until red-hot and then dipped in water. Thanks to this, the metal acquires varying degrees of hardness and elasticity.
• Possibility of “releasing” by heating to red heat and then slowly cooling.
• Ability to be processed with a forging hammer in a heated state, since the steel is perfectly forged.
• Possibility of cutting metal into thin strips.

The softness of steel is directly proportional to the amount of carbon in its composition. The less carbon there is in a metal, the softer and easier it is to process. The softness of steel increases during annealing, that is, “releasing” the metal. To do this, the steel is heated red-hot and then subjected to a slow cooling procedure.

Steel for the manufacture of various products and artistic processing is produced in the form of graded material. For engraving and minting, U8 and U10 steels are most often used, where the letter “U” indicates the amount of carbon in the alloy.

The blade of the knives is made of stainless carbon steel

Non-ferrous metals

Non-ferrous metals are much more expensive than ferrous metals because they have many unique properties. The main one is the lack of reaction with a magnet, that is, non-ferrous metals are not attracted and are not magnetized. In addition, most of them are practically resistant to oxidation, so the products are characterized by a long service life.

The production of non-ferrous metals for artistic processing is carried out in various forms:

• Ribbons
• Stripes
• Chushki
• Tubes
• Wire
• Rods
• Sheets

Let's look at the characteristic features of the most popular non-ferrous metals among craftsmen:

• Copper is a fairly soft metal of a beautiful red-orange hue, characterized by increased ability to forge and has high electrical conductivity and the ability to conduct heat. Processing copper is not particularly difficult, but the craftsman must keep in mind the high viscosity of this metal.

Copper can be soldered using tin and braze. Copper sheet is the main material for chasing and engraving work. Copper wire is used to make decorative items and openwork sculptures.

Copper sink

• Bronze is an alloy of copper and tin. The quantitative tin content affects the color of the alloy, which can take on pink, red, yellow or gray shades. If a bronze product is covered with a layer of patina (a decorative coating of copper oxide), then it acquires a noble smoky-greenish tint and looks ancient and truly expensive. Bronze is most often used for inlay and foundry work.

Sheet bronze

• Brass is an alloy of copper and zinc. The shade of the metal depends on the amount of zinc. According to its qualitative characteristics, brass is a harder alloy than pure red copper, therefore its degree of malleability is much lower. Compared to copper, brass has some brittleness, but at the same time it is more elastic.

Brass can easily be processed in various ways; in particular, it can be used for the manufacture of thin parts in inlays, as well as jewelry of various configurations. For embossing work it is used in sheet form.

Embossing on brass

• Zinc is perfect for casting both in its pure form and in alloys with other metals. Pure zinc is difficult to forge, but it is easy to solder, engrave, and machine with a variety of tools. The melting point is 419* C.

Sheet zinc

• Tin is a non- ferrous metal, known for a long time for its softness and ductility. Its melting point is only 252* C. As a component, tin is included in various types of bronze. When broken, tin produces a characteristic, recognizable crunch. Pure tin and its alloys are ideal for making inlays. Tin is also used for tinning and soldering dishes, both in its pure form and in alloys with lead. At the same time, its oxidation products are harmless.

Set of tin soldiers

• Aluminum is a silvery-white non-ferrous metal that melts at a temperature of about 658* C. A characteristic feature of aluminum is its lightness and ease of metal processing. Cast aluminum is quite brittle, but when rolled (annealed) it acquires the desired ductility.

Aluminum crafts from Madagascar

• Lead is a soft non-ferrous metal with a bluish-gray tint. It melts at a temperature of 327* C and resists corrosion well. However, it should be noted that lead oxides are poisonous. Lead is suitable for foundry work and the manufacture of molded products.

Lead (standard)

• Silver is also a non-ferrous metal, but it is also a precious metal. Pure silver is too soft and therefore difficult to work with. For the manufacture of products it is used in the form of alloys with copper. Silver inserts are used in inlays, engraving, embossing and niello.

Antique silver items

Let's consider some properties of metals that affect the quality of artistic products:

• Malleability of the metal - Malleable ductile metals require greater cutting force, but their toughness must be taken into account. A piece of copper or lead needs to be chopped to the end, but brass, zinc or steel can be chipped with a chisel and then simply broken. Harder brass gives a smooth surface when turned, while aluminum or copper seems to drag on the cutter.
• Brittleness is the ability of solid materials to fracture due to mechanical stress without noticeable plastic deformation. This property is the opposite of plasticity. Heavily hardened steel, as well as many types of brass and bronze, are very brittle and will break into pieces under strong impacts. The brittleness of a metal is not always a sign of its hardness; for example, a zinc casting is brittle but not hard. A hardened steel knife is both hard and brittle.
• Elasticity is the property of metals to restore their shape and volume after the cessation of external forces or heating that caused the deformation. To a large extent, special grades of steel have this property.
• Melting when heated - the ability of a metal to melt when heated is an important quality, since melting is considered one of the most accessible and cheapest ways to produce metal products. Parts of huge machines and small metal sculptures are made in the same way.

If there is a need to harden a part while maintaining the viscosity of the metal, craftsmen use high-frequency currents. In this case, the part is hardened to a depth of several millimeters. However, the rest of the metal mass inside the product remains unchanged. And finally, metal parts can be processed without heating - for example, by engraving and metal carving.

Silver products

Source: http://design-fly.ru/materiali/svojstva-metallov.html

Difference between steel and iron

Steel differs from iron in the presence of carbon. Essentially, steel is an alloy of carbon and iron. Steel contains a fairly high percentage of carbon. Iron is a simple substance, so it does not contain carbon. In nature, pure iron is very rare. Moreover, even humans almost never use pure iron to produce products.

articles

Iron is a chemical element and a simple substance that is practically never found or used in its pure form.

Steel is a special alloy based on iron enriched with various chemical elements. Steel contains up to 2.14% carbon. Iron alloys enriched with carbon, losing viscosity and ductility, acquire hardness and strength.

Comparison

Iron in its pure form is not used. In this form, it is used in laboratories for chemical experiments and serious scientific experiments. The fact is that the confusion of the concepts of “iron” and “steel” occurred among the people. People identified steel with iron, calling both “iron.” When people talk about iron, they are actually talking about steel.

Depending on the purpose for which the steel is intended (an alloy of iron and any chemical elements), it is given the required properties that best meet the prevailing operating conditions.

Everything depends on the chemical elements that will be added during steel smelting and on how much of them will be added to the alloy. Steel is enriched with molybdenum and cobalt, tungsten and chromium, as well as other elements. By changing the composition of steel, titanium alloy and stainless steel are produced.

In addition, they produce alloy steels used in aviation, where structures cannot do without heavy-duty elements, for example, landing gear. Alloying elements and carbon are added to high-alloy steel. Steels with alloying elements contain a minimum of 45% iron.

Iron, unlike steel, is easily susceptible to corrosion.

Conclusions TheDifference.ru

1. Iron is significantly different from steel. It has completely different properties.
2. Iron, unlike steel alloys, is more susceptible to corrosion.
3. Pure iron is not used in everyday life or industry. Pure iron is worked only in chemical laboratories.

Source: https://TheDifference.ru/chem-otlichaetsya-stal-ot-zheleza/

What kind of steel is called boiling - Metalist's Handbook

Previously, we looked at the structure of steel (iron-carbon system), the deformation and destruction of metals, the influence of various impurities on its properties, etc.

In this publication we will consider types of steel according to the degree of deoxidation.

general information

So, steel is an alloy of Fe + C, (C – no more than 2%) + other elements. Steel is divided into carbon and alloy, taking into account the chemical composition, and based on the application - structural and instrumental . Special steels with specific characteristics are also produced for use in aggressive environments; such steels include heat-, corrosion-, and acid-resistant steels.

 The quality of steel is determined by the production method and the amount of bad impurities and is divided into ordinary, high-quality, enhanced and high quality.

Chemical composition of ordinary quality steels

There is a typification based on the nature of solidification in the mold and the geometric shape of the ingot (mold shape). There are calm, semi-calm and boiling .

Carbon steel

 Carbon steel is smelted without the addition of any alloying elements and is of ordinary and high quality.

Standard quality steels are usually divided into the following groups:

• group A – ensured by mechanical properties. Products made from steels of this group are used for subsequent welding, forging, etc. Moreover, the declared fur. properties may change. (St3, St5kp.).

• group B – steel is provided according to chemical requirements. composition. It is used for the manufacture of parts, during processing of which the mechanical characteristics determined by the composition may change.

Steel from group B is divided into 2 categories:

• 1st - the content of C, Si, Mn was established; limited content: S, P, N, As,
• 2nd - the amount of Cr, Ni, Cu is additionally limited.

 • group B - ensured by mechanical characteristics and content of chemical elements. Used in the production of welded parts.

Divided into six categories.

Group B is designated as follows: steel grade, degree of deoxidation, category number. 

 They have the same composition as steel of category 2, group B. 

Steel marking

Considering, as an example, the marking of steel St5ps (structural carbon steel of ordinary quality).

We determine that:

1.  this steel belongs to group A (since the category is indicated before the letters St (VSt1, VSt2), and only group A is not indicated).
2.  number 5 - determines the conditional number of the brand based on the chemical. composition and mechanical properties.
3.  ps is the degree of deoxidation.

If after the number defining the steel grade there is a letter G, then the steel contains a suspended amount of manganese. (St25G2S)

Degrees of steel deoxidation

 There are 3 degrees of steel deoxidation.

The deoxidation process allows you to restore iron oxide and bind dissolved oxygen, thus reducing its harmful effects.

Boiling steel

Boiling steel is not completely deoxidized. During casting into molds, it boils due to the abundant release of gas, so it is the most contaminated with gases and inhomogeneous. T.

The mechanical properties of the ingot may differ , since the distribution of chemical elements throughout the ingot is not uniform.

The head part of the ingot contains the largest amount of carbon and various bad impurities (such as sulfur or phosphorus), which requires removal of part of the ingot (5% of the total mass).

The accumulation of sulfur in certain areas can cause a crystallization crack to appear along the seam. In these areas, steel is less resistant to aging and is most brittle at sub-zero temperatures. silicon in boiling steel does not exceed 0.07%.

So, we can say about boiling steel that it is quite brittle, has poor weldability and is most susceptible to corrosion. Therefore, in order to improve the characteristics of steel, it is deoxidized with silicon (0.12-0.3%), aluminum (up to 0.1%) or manganese (deoxidation is also possible with other chemical elements that dynamically react with oxygen).

Boiling steel is quite brittle, has poor weldability and is most susceptible to corrosion. 

The deoxidation process allows you to restore iron oxide and bind dissolved oxygen, reduce its harmful effects, while maintaining a high temperature of the steel for a long time, which promotes maximum gas and slag removal, as well as obtaining a micro-grained structure due to the formation of crystallization areas. Due to the formation of these foci, the quality of steel improves.

  Liquation is the formation of a heterogeneous chemical structure of steel that occurs at the moment of crystallization. I distinguish two types of liquation: intracrystalline and dendritic. This phenomenon was first discovered by Russian metallurgists N.V. Kalakutsky and A.S. Lavrov in 1866.

Calm steel

The steel obtained as a result of deoxidation is called calm steel. silicon in mild steel is at least 0.12%, and the presence of non-metallic inclusions and slag is minimal.

Mild steel ingots have a dense, homogeneous structure and, accordingly, improved mechanical properties. Mild steel is excellent for welding and also has better resistance to impact loads. It is more homogeneous. It is suitable for the construction of supporting metal structures (due to its resistance to brittle fracture) that are subject to heavy loads.

Mild steel is excellent for welding and also has better impact resistance and is more uniform.

Semi-quiet steel

 Semi-quiet steel is intermediate in quality indicators.

It is semi-deoxidized and crystallizes without boiling, releasing a sufficient amount of gas and having fewer bubbles than boiling steel. Therefore, semi-quiet steel has average quality indicators (as close as possible to calm steel), and sometimes replaces calm steel.

The cost of semi-quiet steel is slightly lower than that of calm steel, and the yield of high-quality rolled products from such ingots is 8-10% better.

The quality indicators of semi-quiet became closer to calm.  

Semi-quiet steel hardens without boiling, but with the release of a large amount of gas. In such an ingot the content of bubbles is less than in a boiling ingot, but more than in a calm one.

 Since the production of boiling steel is cheaper than calm and semi-quiet steel, it is widely used for the production of the least critical rolled metal products, such as wire rod, strip, angle, and hardware.

: 11.03.2016

Source: https://ssk2121.com/kakuyu-stal-nazyvayut-kipyaschey/

Top 10 best comics published in Ukraine in 2019

In recent years, a somewhat paradoxical situation has developed: on the one hand, millions of Ukrainians either know nothing about comics, or, despite regularly visiting cinemas with blockbusters based on the plots of the Marvel and DC universes, they still consider comics to be entertainment, if not people with bad taste, then certainly worthy only of children of primary school age.

On the other hand, the number of readers is steadily growing, and Ukrainian publishing houses are publishing more and more comics every year, not only localized ones, but also from their own, Ukrainian authors. New stores are opening - not only in Kyiv, but also in the provinces. Well, the fact that crowds of geeks from young to old flock to the capital’s ComicCon Ukraine is, as they say, practically part of the landscape.

The editor-in-chief decided to collect the top major comics and graphic novels released in Ukraine in 2019. If the names below don’t tell you anything, go and read, most of the works presented in the list are a large cultural layer that has finally reached us and which is worth at least a superficial acquaintance with for any person who loves to read.

So, the top comics published in Ukraine in 2019 according to the Editor in Chief:

Hellblazer. The one who is going through hell. Book 1

Vertigo / Ridna mova

The publishing house Ridna Mova decided not to waste time on trifles and begin to acquaint neophytes (and satisfy fans who have suffered from anticipation) with the adventures of the blond British magician/occultist (the main hater of the phrase “Kurts die early” in comics) John Constantine from a weighty 392-page volume. The publisher included stories written by Garth Ennis in the early 90s (even before he thundered with his blasphemous Preacher).

In general, for those readers who are familiar with the character solely from the bright and stupid film adaptation with Keanu Reeves, The One Who Walked Through Hell is perfect. Unless, of course, they are confused by black magic, liters of alcohol and tons of cigarettes on the pages of this book.

Batman. Curses and Batman White Face

DC Black Label / Ridna mova

In the fall of 2018, DC Comics, one of the two monsters of the global comics industry, waved its imaginary saber and finally closed its legendary division - the Vertigo imprint, which for years published all the non-format, non-banal, oozing with blood and swearing/blasphemy comics. In general, absolutely not suitable for the parent company. Instead of Vertigo it is now DC Black Label.

And Ridna Mova published two locomotive, so to speak, comics of the updated imprint - The Damned and the White Knight. The first one was written/drawn by the already united duo of Brian Azzarello and Lee Bermejo (the comic is like a continuation of their already legendary Joker ten years ago). And, perhaps, the Dark Knight has never been looked at from such a creepy and frightening angle.

Moreover, his partner in the search for the killer of the Joker in Damned corresponds to horror like no other - the same John Constantine.

The White Knight is a great and interesting experiment by Sean Murphy, who asked questions that had not occurred to other writers: what if the Joker’s madness is still reversible, and how then will Batman behave - what if he is not a hero without fear and reproach? And what can Gotham and other superheroes and supervillains expect from this situation? A special plus is that there are two Harley Quinns in the comic.

Superman. Red Syn

DC / Ridna mova

Despite all the fears of fans about the fact that Red Son will not be published in Ukrainian due to the law on decommunization, the punishing hand of Mr. Vyatrovich and his subordinates never reached the comics. And so, the legendary work of Mark Millar, revealing the story of Superman, whose capsule fell not near a Kansas farm, but on a Ukrainian collective farm, was finally published.

The author’s bold assumption was fully justified - a comic book about how Superman becomes Stalin’s successor and in his own way proves to the whole world the old maxim “And under communism everything will be great” is read in one breath.

Not to mention a bunch of references to classic stories about the Man of Steel or the history of Batman (and a host of other famous DC characters) shoveled in the best possible way.

Bonus - all lovers of Ukrainian literature will find a small Easter egg with a twisted quote from not just anyone, but T. G. Shevchenko himself.

Gauntlet of Infinity

Source: https://glavred.info/comics/10136720-top-10-luchshih-komiksov-izdannyh-v-ukraine-v-2019-m.html

Steel: iron + carbon +

The “everyday” definition of steel goes something like this: “A hard and durable iron-based metal alloyed with a small amount of carbon and often other metals such as nickel, chromium, and manganese.” Although it cannot be said that this definition is completely incorrect, it hardly adequately reflects the concept of “steel”.

A more precise definition of steel might be: “An iron-based alloy that is highly deformable within a certain temperature range and contains carbon and often other alloying elements. In carbon and low-alloy steels the maximum carbon content is about 2%, in high-alloy steels - up to 2.5%. The dividing line between low-alloy and high-alloy steels is usually 5% metal alloying elements.  

Three phases of steel - ferrite, cementite and austenite

In principle, all steels are mixtures, or rather alloys, of iron and carbon. However, even the most common steels, so-called general purpose steels, have small but controlled amounts of manganese and silicon, as well as small and usually unavoidable amounts of phosphorus and sulfur. carbon in general purpose steels is usually from 0.05 to 1.0%.  

The mechanism of alloying iron with carbon differs from other alloy systems in that it is a two-stage process. In the first stage, iron combines with 6.67% carbon to form iron carbide, more commonly called cementite. Therefore, at room temperature, ordinary steel contains a mixture of cementite and ferrite. Both of them are phases.

A phase is a physically homogeneous and separated part of a material system. When steel is heated to 725 ºC, cementite, cementite, dissolves in the iron and a new phase is formed - austenite. Note that one should not confuse “steel phases” and “steel structures”.

Any steel can have only three phases, while there can be several structures, as well as mixtures of them.        

Steel classification

It is impossible to determine the exact number of steel compositions that currently exist. There are at least a thousand of them. There is no strict classification of steels. However, most often steel is divided into five groups, which suits most specialists who work with steel.

These five classes are:

carbon steels; alloy steels, sometimes called low-alloy steels; stainless steels - standards call them “corrosion-resistant”; tool steels;

special steels,

Special steels include steels with special properties that are needed for their use in specific operating conditions. In addition, these may be steels that are very similar to steels from the first four groups, but are still so different from them that they require a separate alloy designation.   

Why is steel the main one?

It would be unfair to claim that any one metal is more important than another. For example, without aluminum and titanium there would be no modern aircraft and spacecraft.

Steel, however, is much more widely used than any other metal. It is generally believed that the reason for steel's dominance is due to the abundance of iron ore and the ease with which iron can be extracted from the ore. Both are wrong. Iron is not the most abundant element. It is not so easy to extract it from ore, but copper, for example, is found in almost pure form in some areas of the world.  

What makes steel such an important material is its incredible flexibility in its processing and application. This flexibility is given to it by the variety of options for its structure and methods of deformation and heat treatment to achieve them.

Wide possibilities for the use of steel are provided by two of its important metallurgical phenomena:

1) iron is an allotropic element, that is, it can exist in more than one crystalline form;
2) the size of a carbon atom is only 1/30 of the size of an iron atom.

Iron is the basis of steel

All pure metals, as well as alloys, have individual phase diagrams, which are more often called phase diagrams. As a rule, the percentage of alloying element in the alloy is plotted along the horizontal axis. Temperature is plotted vertically. The diagram of pure iron is a straight line. When pure iron is cooled, it changes from one phase to another at a constant temperature.   

Pure iron solidifies at 1538ºC to form a crystalline structure called ferrite or delta iron. This phase has a body-centered cubic atomic lattice. With further cooling, reaching a temperature of 1395 ºС, the atoms are rearranged into a 14-atomic lattice, which is called gamma iron.

As cooling continues below 910°C, the iron structure returns to the 9-atomic lattice or alpha iron. The change at 770°C simply denotes a change from non-magnetic iron to magnetic iron and is not a phase change.

The entire field below 910 °C is ferrite down to room temperature and below.

Ferrite that forms above austenite is often called “delta ferrite,” while ferrite that forms below point A3 is called alpha ferrite, although structurally both are exactly the same.

The mechanism of allotropy is the most important property of iron, which provides it with the diversity of its structure and the flexibility of heat treatment of steels.

• Metastable iron-carbon phase diagram
• Austenite transformation

Source: https://steel-guide.ru/metallografiya-stali/stal-zhelezo-uglerod.html

Basic properties and characteristics of steel

In industrial production, combinations of several chemical elements are often used to create the highest quality materials. This approach is especially common in metallurgy, where the resulting alloys are able to work under conditions that are beyond the control of pure metals.

The combination of several elements allows you to achieve unique properties that are necessary in a particular industry. One of the most common alloys is steel. It is obtained by combining iron with carbon. Also, the mass fraction of the material includes a small amount of impurities. If necessary, alloying additives are introduced into the alloy or the metal surface is coated with a protective layer.

Chemical composition of steel

The properties and characteristics of steel depend on the quantitative composition of the chemical elements in its structure. Carbon gives the material hardness and toughness, but its increased content leads to brittleness and impairs weldability.

The highest quality steel is obtained after annealing treatment, when carbon is introduced into the structure of the iron metal lattice at the molecular level and forms a stable cementite compound. silicon in the alloy increases fluidity and strength, as well as elasticity. But an excess of this element impairs weldability and impact strength.

Manganese in a mass fraction of up to 2% can increase the strength of the material. At higher percentages, welding becomes difficult.

Chromium protects steel from oxidation and significantly extends its service life. But if heat treated incorrectly, it forms carbide, which interferes with welding. Nickel improves ductility, toughness and malleability, and is also one of the few elements whose increased content does not lead to side effects. Molybdenum increases the thermal resistance of steel, as well as the maximum permissible loads, therefore, it is actively used as additives in structural alloys.

Vanadium improves toughness and elasticity, actively promotes the hardening process, but impairs weldability. Tungsten adds hardness and resistance to the material when working at high temperatures.

Titanium increases the corrosion resistance of steel, but excess titanium can lead to hot cracks during welding. Copper increases the corrosion resistance and malleability of the metal and does not have negative effects when in excess.

In addition to the listed elements that give steel positive properties, there are also substances whose presence only carries a negative load.

Sulfur increases the brittleness of the material at high temperatures and makes weldability difficult. Phosphorus increases the brittleness parameter at normal temperatures and also impairs weldability. Nitrogen, oxygen and hydrogen negatively affect strength and lead to rapid aging of steel. Negative elements must be kept to a minimum so that the quality of the material meets the needs of the market.

Characteristics of steel

The hardness of steel depends on the mass fraction of carbon, as well as the amount of special additives. Hard materials are mainly used in cases where they will not be subject to dynamic loads, since the brittleness of the alloy usually increases with hardness.

The tensile strength of steel is 60 kilograms per square millimeter. The remaining strength values ​​directly depend on the grade of material. Resistance to a certain type of negative impact is achieved by hardening the metal or introducing the necessary additives into the alloy.

The tensile strength of steel is always reflected in the marking so that the buyer can quickly select the material he needs. The resistivity of steel varies from 0.103 to 0.137 Ohm * millimeter squared / meter. The value depends on the quantitative content of chemical elements in the alloy.

For electrical steels, the resistance indicator is 0.25-0.6 Ohm * millimeter squared / meter. Such a high value compared to conventional steel is explained by operating conditions and meets technical requirements.

The calculated resistance of steel can be different even for one batch of products, since the amount of impurities is not distributed evenly throughout the entire structure of the alloy.

Steel conductors are used very rarely in practice, since there are metals that have much better parameters necessary for use in electrical engineering. But electrical steel is one of the main materials used in the manufacture of housings for electrical appliances and transformers.

The thermal conductivity of steel is at a high level, which allows the material to be successfully used in heating systems. With increasing temperature, this figure decreases slightly, but the total losses are not critical compared to energy costs.

Of course, there are metals and alloys with much higher thermal conductivity parameters, but their use is unprofitable due to the high costs of their production.

The specific heat capacity of steel is 0.462 kilojoules/kg*Kelvin. This is a good indicator for metal. This characteristic shows how much thermal energy needs to be transferred to the body in order for its temperature to change by one degree.

That is, the lower this indicator, the faster the substance heats up. The actual value of the heat capacity of steel allows us to once again prove the justification of its use in heating networks.

In addition, steel retains the heat received very well and cools slowly, so less fuel is needed to maintain the temperature at the desired level.

The steel-to-steel friction coefficient at rest is 0.15 without the use of lubricant and 0.1 with it. When sliding, this parameter will be 0.15 and 0.05, respectively. The chemical properties of steel depend on the quantitative and qualitative content of elements in the alloy. If it is necessary to operate a material in an aggressive environment, additional additives are introduced into its composition to prevent or greatly slow down the occurrence of destructive chemical reactions.

Source: https://promplace.ru/vidy-metallov-i-klassifikaciya-staty/svoistva-i-harakteristiki-stali-1547.htm

What are the types and types of metals and their alloys?

In construction, industry and other areas of human life, various types of metals are often used. They differ from each other in the properties by which they are selected and used in a particular area. Materials are obtained in a variety of ways. Certain types of metals are combined together to create alloys that have unique physical and chemical properties.

Characteristics and Signs

Metals are a group of elements in the form of simple substances that have characteristic metallic properties. In nature they are present in the form of ores or compounds. Sciences such as chemistry, physics and metallurgy study the characteristics of these materials.

Metals have a combination of different properties. Mechanical factors determine their ability to resist deformation and destruction. Technological methods help determine the ductility of materials to various types of processing. Chemical properties show their interaction with different substances, and physical properties indicate their behavior in thermal, gravitational or electromagnetic fields.

Metals are classified according to the following properties:

• Hardness is the resistance of a material to penetration by another.
• Strength - preservation of shape, structure and size after exposure to dynamic, static and alternating loads.
• Elasticity is a change in shape without violating integrity during deformation and the possibility of returning to its original form.
• Plasticity is the retention of the resulting shape and integrity under the influence of forces.
• Wear resistance - maintaining external and internal integrity under the influence of prolonged friction.
• Viscosity - maintaining integrity under increasing physical stress.
• Fatigue is the number and period of cyclic impacts that a metal can withstand without changing its integrity.
• Heat resistance - resistance to high temperatures.

The primary characteristic of metals is the negative conductivity coefficient of electricity, which increases when the temperature drops, and is partially or completely lost when the temperature rises. Secondary characteristics of materials are metallic luster and high melting point. In addition, some types of metal compounds can be reducing agents in redox reactions.

Metallic properties are interrelated, since the components of the material affect all other parameters. Metals are divided into ferrous and non-ferrous, but they are classified according to many criteria.

Group with iron and its alloys

Ferrous metals are characterized by impressive density, high melting point and dark gray color. This group mainly includes iron and its alloys. To impart specific properties to the latter, alloying components are used.

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Subgroups of ferrous metals:

• Iron - iron, cobalt, manganese, nickel. They are usually taken as a base or as an additive to alloys.
• Refractory - tungsten, molybdenum, titanium, chromium. They melt at a temperature higher than the melting level of iron. Alloy steels are obtained from refractory varieties.
• Rare earths - lanthanum, neodymium, cerium. They have related chemical properties, but differ in physical parameters. Used as an additive to alloys.
• Uranium (actinides) - actinium, neptunium, plutonium, thorium, uranium. Widely used in nuclear energy.
• Alkaline earths - calcium, lithium, sodium. They are not used in free form.

Metals of the ferrous group are represented by iron alloys with different carbon content and the content of additional chemical elements: silicon, sulfur or phosphorus. Popular materials are steel and cast iron. Steel contains up to 2% carbon.

It is characterized by good ductility and high technological performance. In cast iron, the carbon content can reach 5%.

The properties of the alloy may differ with different chemical elements: with the content of sulfur and phosphorus, brittleness increases, and with chromium and nickel, cast iron becomes resistant to high temperatures and corrosion.

Colored varieties

Non-ferrous metals are more in demand than ferrous metals, since most of them are raw materials for the production of rolled metal. This group of materials has a wide range of applications: they are used in metallurgy, mechanical engineering, radio electronics, high technology and other fields.

Classification by physical parameters:

• Heavy - cadmium, nickel, tin, mercury, lead, zinc. Under natural conditions, they are formed in strong compounds.
• Lightweight - aluminum, magnesium, strontium, titanium and others. Characterized by a low melting point.
• Noble ones - gold, platinum, rhodium, silver. They are characterized by increased resistance to corrosion.

Non-ferrous metals are characterized by low density, good ductility, low melting point and predominant colors (white, yellow, red). Various equipment is made from them. Since the strength of the materials is quite low, they are not used in their pure form. Light alloys for various purposes are produced from them.

Materials of this group are characterized by impressive atomic weight and density, exceeding that of iron.

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Copper, which acts as a conductor of electric current, is in great demand.

It is characterized by a pinkish-red hue, low resistivity, good thermal conductivity, low density, excellent ductility and corrosion resistance. In the technical field, copper alloys are used: bronze (with the addition of aluminum, nickel or tin) and brass (with zinc).

Bronze is used in the production of membranes, round and flat springs, worm gears and various fittings. Tapes, sheets, wire, pipes, bushings, and bearings are made from brass.

The group of heavy metals is one of the main causes of environmental pollution. Toxic substances enter the oceans through wastewater from industrial plants. Some varieties of the heavy group can accumulate in living organisms.

Mercury is a highly toxic metal for humans. When coal is burned at power plants, its compounds pass into the atmosphere, and then are converted into sediment and end up in water bodies. Inhabitants of freshwater and marine systems accumulate large amounts of a dangerous substance, which leads to poisoning or death of people.

Cadmium is considered a trace element and a fairly rare element that can enter the ocean through wastewater from metallurgical plants. This substance is present in small quantities in the human body, but at high levels it destroys bone tissue and leads to anemia.

Lead is present in a dispersed state almost everywhere. When there is an excess of metal in the human body, health problems are observed.

Soft types

Silver-white aluminum is characterized by lightness, high corrosion resistance, good electrical conductivity and ductility. The characteristics of the material have made it useful in aircraft construction, the electrical industry and food production. Aluminum alloys are used in mechanical engineering.

Magnesium has low corrosion resistance, but the lightweight material is indispensable in the technical field. Alloys with this metal use aluminum, manganese and zinc, which are easy to cut and have high strength. Magnesium alloys are used in the production of cases for cameras, engines and other devices.

Titanium is used in mechanical engineering, the rocket industry and the chemical industry. Alloys containing this substance are characterized by low density, excellent mechanical properties, corrosion resistance and flexibility in pressure treatment.

Noble materials

Some types of metals are rarely found in nature and require labor-intensive extraction methods. The noble group metals are:

• Gold.
• Silver.
• Platinum.
• Rhodium.

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People learned about gold back in the Stone Age. The most expensive metal in the world can be found in nature in the form of nuggets, which contain a small amount of impurities. It is also found in alloys with silver.

Gold has thermal conductivity and very low resistance. Due to its good malleability, the material is used in the manufacture of jewelry.

Silver comes second in value after gold. In nature, it is usually found as silver ore. Silver is characterized by softness, ductility, thermal and electrical conductivity.

Platinum, discovered in the mid-20th century, is a rare material that can only be found in deposits of various alloys. It is quite difficult to obtain. The value of the metal lies in the fact that it is not affected by acids. When heated, platinum does not change color and does not oxidize.

Rhodium is also a noble metal. It has a silver color with a blue tint. Rhodium is resistant to chemical influences and temperature changes, but the fragile metal deteriorates under mechanical stress.

Hardness classification

Metals are also divided into hard and soft.

The hardest pure material in the world is chromium . It belongs to the refractory varieties and lends itself well to mechanical processing. Another solid element is tungsten.

It is characterized by high melting point, heat resistance and flexibility. Various parts are forged from it and small elements necessary for lighting fixtures are made. Tungsten is often present in heavy alloys.

Hard metals are not only difficult to mine, but also difficult to find on the planet. They are mainly found in meteorites that fell to Earth.

The softest metals include potassium, sodium, rubidium and cesium. Also in this group are gold, silver, copper and aluminum. Gold is present in marine complexes, granite fragments and the human body. External factors can destroy valuable metal.

Soft silver is used in the manufacture of dishes and jewelry. Sodium is widely used in almost every industrial sector.

Mercury, the softest metal in the world, is used in the agricultural and chemical industries, as well as electrical engineering.

Source: https://vtothod.ru/klassy/kakie-byvayut-vidy-i-tipy-metallov-i-ih-splavov

When will Liverpool win the championship? We consider four scenarios

After Manchester City drew at home to Crystal Palace, Liverpool moved 13 points clear of second place. At the same time, Jurgen Klopp's team still has two games in hand. Can you imagine missing out on such a colossal advantage?

Experts and neutral fans are already formulating the question of the title race in the Premier League this way: not if, but when will Liverpool win the title?

As for the Merseyside fans themselves, after what happened to Benitez's team in 2009 and Rodgers' team in 2014, they are unlikely to start celebrating until the advantage becomes irrecoverable.

Let's analyze four scenarios from Liverpool's point of view - optimistic, realistic, pessimistic and fantasy.

Optimistic scenario

In terms of results, Liverpool has nowhere to improve; it is enough to continue at the current pace. Currently, Jurgen Klopp's players score an incredible 2.9 points per match (20 wins + 1 draw).

Manchester City, who scored a record 100 points at the end of the season, were moving at a pace of 2.63 points per game.

This means that if Liverpool achieves the same results in the second half of the season as in the first, they will set a new Premier League record of 110 points.

If we assume that City and Leicester will collect points at their current pace (2.09 points per game for the former, 2.05 per game for the latter), then the title will mathematically be won in round 31 (end of March) after positive result in the home game with Crystal Palace.

Is it possible to go the entire distance without slumping? History says no. But Liverpool 2019 really looks like an unprecedented team.

Realistic scenario

If the possible outcome of 110 points has you dizzy, let's add a pinch of skepticism to our reasoning. Klopp, of course, is Kojima, and his players are obsessed with winning the Premier League, but let's not forget those games that Liverpool pulled out in the last minutes in the fall.

Even if we assume that the quality of the Premier League leader’s play does not decline much, he cannot be so lucky all the time. The Champions League playoffs will begin, and the physical and psychological stress on the players will increase. Let's drop Liverpool's figures to last year's - 2.55 points per game. This is still the level of superheroes, but those who are made of flesh and blood - Batman or Spider-Man, and not a visiting comrade from the planet Krypton.

We will raise Manchester City's performance to 2.3 points per game. This is still not a championship schedule, but it is better than what we have now. In the end, the injured will return, Guardiola will try new schemes. The expected points statistic suggests that City should have scored 3.7 points more than they currently do - this correlates with our adjustment.

The picture will not change radically. Liverpool, with last year's schedule, will still win the Premier League with a new record of 104 points, clinching the title after the 32nd round (beginning of April). By the way, in the 32nd round, Liverpool plays Manchester City away. This is the most appropriate option for winning the title, isn’t it?

It turns out that even the realistic scenario looks too optimistic. For this case we have

Pessimistic scenario

Liverpool is far from reaching the knockout stages of the Champions League, and this is causing the physical decline that has overtaken the team to prolong. Salah, Alexander-Arnold and Alisson are injured. All those moments that before the New Year were in favor of the Merseyside team are starting to work out in favor of their opponents.

Liverpool scores 2.05 points per game, the same as current Leicester. This is also a very good indicator, but last season’s vice-champions look like mere mortals. Guardiola is finally sorting out City's personnel problems, Laporte is ahead of his doctors' recovery deadlines, and the Manchester team is starting to move to last year's pace of 2.58 points per game.

Just-just-just this is not enough. Even if City starts consistently gaining more points than Liverpool, it will still be impossible to catch up with Klopp. According to this scheme, Liverpool will win the title based on the results of the 35th round (end of April) after the home game with Burnley. The final result - 95 points - will not allow City to get within 8 points of the finish line.

So what needs to happen for Liverpool to not win the title after all?

Horror movie script

A strange virus wipes out half of Liverpool's starting lineup; even Dr. House cannot understand its nature. Alisson says he has found Jesus and is retiring from his professional career. Klopp is starting to hear voices. What's worse are the voices of Benitez and Rodgers. Liverpool is starting to score 1.5 points per game - this is somewhere between the current Manchester United and Wolverhampton.

Manchester City is undergoing a dramatic transformation. Guardiola joins the team as a free agent, enters the defensive zone and thereby solves the problems in defense. Aguero eclipses Messi in terms of performance over the remaining months. City are gaining 2.63 points per game, the same as in their record-breaking season the year before.

The teams are approaching the last round closely - Liverpool has 85 points, City has 84. Liverpool plays away in a draw with Newcastle, and City bombs Norwich at home and wins the championship. Hospitals in north-west England are overcrowded.

Which scenario will work in the end? You can’t look at the last page without a time machine, but the first lines can be read today in the game between Liverpool and Manchester United.

Source: https://matchtv.ru/football/matchtvnews_NI1141800_Kogda_Liverpul_oformit_chempionstvo_Rassmatrivajem_chetyre_scenarija