Food grade aluminum
Aluminum is one of the most important non-ferrous metals of our time. In terms of global production, aluminum is in second place after iron. In terms of prevalence in the earth's crust, it ranks 1st among metals and 3rd among elements after oxygen and silicon. Aluminum occurs in nature in the form of compounds. The main minerals from which aluminum is obtained are bauxite, nepheline, alumina, and feldspar.
Aluminum was discovered as a compound in 1805. It was obtained in its pure form in 1825 by the Danish physicist Oersted by electrolysis.
An interesting fact is that before the discovery of the industrial method of production, aluminum was more expensive than gold.
The modern production method, the Hall-Heroult process, was developed in 1886, but due to the high energy costs it remained unpopular for a long time. Industrial production began only in the 20th century.
Features of aluminum
- Light and soft, has a low melting point - about 650 degrees.
- It is not subject to corrosion - a thin film of aluminum oxide is formed on the Al surface, protecting it from destruction. Thanks to this, equipment and products made from sheet aluminum can be exposed to water for a long time without any consequences.
- It is not destroyed by most food acids and alkalis.
- Very plastic. This property allows it to be rolled into very thin foil.
- High thermal and electrical conductivity with a low coefficient of heat capacity determines the absence of deformation when exposed to high and low temperatures and the preservation of high rigidity of products.
- It does not affect the composition of products and components in contact with the surface, which helps preserve the nutritional and beneficial properties of products, vitamins and original microelements.
- Not harmful to health.
- Easy to manufacture, post-process and subsequently use – it polishes, pours, molds, and also cleans and washes well.
Scope of application
- Making dishes.
- Production of containers for storing liquids and mixtures, including canned food and tubes.
- Production of packaging for transportation and storage of food products.
- Production of packaging for cosmetics.
- Production of heat-resistant products, including frying surfaces.
- Manufacturing of machines and molds for the food industry.
- Electrical engineering (stranded wires, cables, transformer windings).
- Making foil.
- Cladding of workshops, storage areas, industrial refrigeration chambers.
- Aircraft construction (duralumin is used).
- Production of industrial, technical and household mirrors (using silumin).
- Aluminizing (coating steel parts with aluminum to impart anti-corrosion properties and protection against oxidation).
- Glassmaking.
Grades of food grade aluminum alloys and additional standards
According to GOST, food-grade aluminum must contain no more than a fixed amount of impurities of other substances: the proportion of lead should not exceed 0.15%, arsenic - 0.015%, zinc - 0.3%, beryllium - 0.05%.
According to GOST, the food industry requires the use of grade A5 aluminum (pure primary aluminum). Alloys such as Ak5M2, AK7, AK9, AK12 are also allowed for use. Other grades of food-grade aluminum can only be used with special permission. A separate GOST is provided for the manufacture of spoons. Also, if the manufacturing technology involves the subsequent application of a special coating, it is possible to use the AMts alloy (GOST 4784).
To summarize, it is worth paying attention to the fact that there are quite a few areas of application for food-grade aluminum sheets. The choice of this metal for production is determined by its technological characteristics, as well as its prevalence among natural resources and as a product on the world market.
Food-grade aluminum has undoubtedly proven itself to be a reliable material in everyday life and production, and its service to humanity will be appreciated more than once.
Source: https://mdmgroup-spb.ru/poleznoe/pishhevoj-alyuminij
Food grade aluminum and its alloy
Aluminum is a non-ferrous metal with low density. The surface of the alloy is silver-white, matte. It is very light and soft, due to which it has a low melting point - approximately 650 degrees. It has found its application in all spheres of human life. It is actively used in the food industry, including for the manufacture of various tableware. It ranks second in production among all metals in the world, after iron.
Aluminum is susceptible to the aggressive effects of acids. Able to dissolve in concentrated alkali solutions. To avoid such phenomena, all aluminum products are covered with protective films. In a crushed dusty state, being in an oxygen environment, it supports active combustion.
A little about the properties and alloys of aluminum
The thermal and electrical conductivity properties of this metal are comparable to gold, silver and copper. Very common in electrical engineering. Multicore wires and cables are made from it, and windings for electric motors and transformers are created.
Aluminum is very ductile, but very fragile. It can be rolled out to a translucent foil. Aluminum ingots can be easily planed and cut.
By introducing appropriate additives, the strength of the alloy can be significantly increased, thereby expanding the range of its applications.
A similar alloy was developed in 1911 by German craftsmen in the town of Düren. This is where the name of the alloy consisting of aluminum, copper, magnesium and manganese comes from - duralumin, or duralumin.
This combination and long-term hardening made it possible to increase the strength characteristics and maintain the same lightness (aluminum is 3 times lighter than steel). Duralumin alloy has found great use in aircraft construction, due to which it has been nicknamed “winged metal”.
To maintain anti-corrosion characteristics, it was coated with pure aluminum.
To eliminate such sputtering, another aluminum alloy with silicon inclusions was developed - silumin. Due to its shine and silvery color, aluminum is used in the production of mirrors, both industrial and technical (for example, for telescopes), and household ones.
Use of aluminum alloys in the food industry
Aluminum is used quite actively in the food industry, as well as in everyday life. It is used to make dishes, all kinds of containers for liquids and mixtures, and to make machines and equipment for food production. For this, food-grade aluminum sheets are usually used.
This is due to the fact that aluminum alloys do not in any way affect the composition of products or components of cosmetics. All vitamins, nutrients, original properties and microelements are completely preserved. In addition, they are not capable of harming human health.
Moreover, in the food industry it is allowed to use only food-grade aluminum and its alloys of certain grades.
Metal alloys containing aluminum can also be used. All grades of this metal that are allowed to be used in the food industry must fully comply with GOST.
Every home had or even has kitchen utensils made of aluminum - spoons, cups, ladles, pots, juicers, meat grinders and much more. Aluminum foil is very popular in the culinary world, which is used for baking meat and vegetables or simply storing and transporting food. This foil is great for packaging sweets, chocolate, ice cream, butter, cheese and cottage cheese.
Many creams and cosmetics, art paint (oil, tempera, gouache and even watercolor) are packaged in food-grade aluminum containers. Food for astronauts is also packed in them. It is safe to say that aluminum, including food grade aluminum, and alloys based on it have become firmly established in our everyday life.
Food grade aluminum is widely used in the production of containers for canned food. Due to this spread, the amount of aluminum waste, idle and decomposing in landfills, increases every year.
Advantages of food grade aluminum
Food grade aluminum has many advantages, among which are the following:
- Not subject to corrosion. Thanks to this, kitchen equipment and tools can remain in water for a long time without harm.
- Food grade aluminum does not deform when exposed to high temperatures.
- Despite its coming into contact with materials having organoleptic properties, there is no change in the properties of the products. All vitamins present in them are also preserved.
- Due to sufficient rigidity, the material does not deform during cooking.
- Food grade aluminum is absolutely harmless to the human body and completely hygienic.
- Dishes made from this material can be used for cooking in ovens and microwave ovens.
Production of utensils and equipment for cooking made of aluminum
Food grade aluminum and its alloys are used in many types of food preparation equipment. Since this metal is distinguished by its ability to form all kinds of alloys, it, as mentioned above, is actively used for the manufacture of a variety of kitchen containers. In addition, it is indispensable in the production of all kinds of heat-resistant products. For example, equipment for kitchens and various frying surfaces of electrical household appliances.
Aluminum has excellent heat conductivity with low heat capacity. In addition, it practically does not deform at high temperatures or during temperature changes.
Due to its low melting point and its ductility, aluminum is actively used for casting various products used in the kitchen.
It is suitable for the manufacture of various surfaces that are distinguished by deep relief, all kinds of complex shapes and products with a large area. For example, it is great for all kinds of baking dishes.
Aluminum alloys and GOST
Food grade aluminum, which is used for the production of cookware and other similar products, can be not only in its pure form, but also in the form of various alloys, each of which has international and state quality standards, which indicate how and for what purposes they can be used .
Food grade aluminum
Each grade of this metal has its own unique chemical composition. According to GOST, without taking into account the A5 grade, alloys such as Ak5M2, AK7, AK9, AK12 can be used in the food industry. All other grades of food grade aluminum are allowed to be used only with special permission.
Grades of metal alloys, including aluminum
You can also use metal alloys that contain aluminum. These include brands AB, AVM, A0, AD1, AD1M, AL22, AL23, AMg22. All these alloys are actively used for making spoons.
Quite often, products made from food-grade aluminum or its alloys must subsequently have a special coating applied. But this can be done with the AMts brand, since its chemical composition fully complies with GOST.
Food grade aluminum has long been firmly established in our daily use. It is impossible to find a kitchen that does not have utensils made from this metal. Reviews about it are only positive, and, apparently, its popularity is not going to decline.
Source: https://FB.ru/article/282347/alyuminiy-pischevoy-i-ego-splav
Use as packaging
Every home had or even has kitchen utensils made of aluminum - spoons, cups, ladles, pots, juicers, meat grinders and much more. Aluminum foil is very popular in the culinary world, which is used for baking meat and vegetables or simply storing and transporting food. This foil is great for packaging sweets, chocolate, ice cream, butter, cheese and cottage cheese.
Many creams and cosmetics, art paint (oil, tempera, gouache and even watercolor) are packaged in food-grade aluminum containers. Food for astronauts is also packed in them. It is safe to say that aluminum, including food grade aluminum, and alloys based on it have become firmly established in our everyday life.
Food grade aluminum is widely used in the production of containers for canned food. Due to this spread, the amount of aluminum waste, idle and decomposing in landfills, increases every year.
Food grade aluminum alloy - Metalist's Guide
the modern food industry without aluminum . But not all products are regulated by GOST. Questions arise when it is necessary to line the inside of a container or box for food products, make a muffin tin, tray, or upholster a counter. What kind of aluminum can be called food grade? For products made of aluminum or aluminum alloys, just open GOST.
GOST 1583–93. P. 3.3
Alloys AK7, AK5M2, AK9, AK12 are used for food products. The use of other alloys for products and equipment in contact with food products and environments must be approved by health authorities in each individual case. In aluminum alloys for food products, the proportion of lead should not exceed 0.15%, arsenic - 0.015%, zinc - 0.3%, beryllium - 0.05%.
GOST 1583–93. clause 4.1.6.1
In the absence of color markings, ingots for the manufacture of products and equipment in contact with food are marked with an additional letter “P” after the designation of the alloy grade.
GOST 17151–81. clause 2.3
Regulates the production of household utensils from sheet aluminum. Utensils must be made from sheets and strips of aluminum grades AD1, AD with a chemical composition in accordance with GOST 4784, aluminum grades A7. A6. A5, A0 with a chemical composition in accordance with GOST 11069 and bimetallic tapes made of aluminum grades AD1, AD (chemical.
composition is regulated by GOST 4784) and steel tape grades 12X18H10T and 08X18N10T with a chemical composition regulated by GOST 5632. If the cookware has an internal coating, it is allowed to make it from sheets and tapes of aluminum alloy grade AMts (chemical composition corresponds to GOST 4784). Fasteners that come into contact with food must be made of the same materials as the cookware.
The chemical composition of fittings (handles, bows, ears, etc.) made of aluminum must comply with GOST 11069, and those of aluminum alloys - GOST 4784.
GOST 51016–97
Regulates the general technical conditions for the production of cutlery made of carbon steel and aluminum alloys. Brittle aluminum cutlery is produced from cast aluminum alloys AK7, AK5M2, AL22 (AMg11), AL23 (AMg6l), and soft cutlery is produced from sheet aluminum of the AD1M, AD1 A0, AVM, AB, and AMg2 grades.
Clause 4.3.1
Cutlery must be made from the materials specified in Table 2.
Table 2 Name of products Alloy grade GOST| All-metal knives and combination knife blades | Steel U8A, U10A | 1435 |
| All-metal forks and the working part of combined forks | Steel: 08kp, 45 Aluminum alloys: A0, AVM, AD1MAD1, AB, AMg2, AK7, AK5M2, AL22, AL23 | 10502163147841583 |
| Spoons | Aluminum alloys: A0, AVM, AD1M, AD1, AB, AMg2, AK7, AK5M2, AL22, AL23 | 21631,4784, 1583 |
| Handles of combination knives and forks | Polypropylene grades: 04P-01010, 05P-01020 Aminoplast class BA Aluminum alloys: A0. AVM, AD1MP lumber from hardwood of the first grade with a moisture content of no more than 12 abs. % | Regulatory document 2.9359216312695 |
| Fittings for combined products (rings, caps, washers, rivets) | Steel grade 20 Aluminum alloy AD1 | 10504784 |
| Note - with the permission of health authorities, it is possible to use other alloys similar to those indicated in Table 2 |
Cutlery
Contact with food products is allowed for primary grade aluminum, A, or technical deformable aluminum grade AD-AD0 (not to be confused with the Al-Mg-Si alloys AD31, AD33, AD35, although forks and spoons are also produced from the AB grade alloy).
GOST allows the use of magnesium alloys in AMg2 sheets and AL22 (AMg6l), AL23 (AMg11) ingots, as well as the Al-Mg-Si AB alloy for the production of forks and spoons. GOST 4784 “Aluminum and wrought aluminum alloys.
Marki" supplements the permitted list of food alloys below with the following clarification.
GOST 4784, clause 3.8
In aluminum alloys that are intended for the manufacture of food products, the proportion of lead should not exceed 0.15%, and the proportion of arsenic - 0.015%. However, GOST 4784 does not indicate the permissible proportion of beryllium and zinc, as GOST 1583 for casting alloys. It is logical that in deformable alloys should not contain lead and beryllium in excess of permissible concentrations, except for AMg5, AMg6, D19, where beryllium is from 0.02% to 0.5% (GOST 1583 allows 0.05%), as well as some brands of welding wire: SvAMG5, Sv1557, SvAMg6, SvAMg61, SvAMg63, where beryllium is from 0.2% to 0.5%.
SNIP in Ukraine
In Ukraine, Sanitary norms and rules 42−123−4240−86 are in force. “Permissible amounts of migration (AQM) of chemical substances released from polymeric and other materials in contact with food products and methods for their determination.” The document contains DCM standards for metals released by polymers, but there are no DCM standards for metal products.
GN 2.3.3.972
The Russian Hygienic Standards - “Maximum Permissible Amounts of Chemical Substances Released from Materials in Contact with Food Products” contain acceptable sanitary standards and a hazard class for the use of aluminum and its alloys:
Name of materialChem. elementsDCM, mg/lMPC of chemicals in drinking water, mg/lHazard class 11.30. Primary aluminum (GOST 11069)| special purity | aluminum (Al) | 0,5 | 2 |
| high purity | |||
| iron (Fe) | 0,3 | ||
| silicon (Si) | 10, 0 | 2 | |
| copper (Cu) | 1, 0 | 3 | |
| technical purity | aluminum (Al) | 0,5 | 2 |
| iron (Fe) | 0,3 | ||
| silicon (Si) | 10, 0 | 2 | |
| copper (Cu) | 1, 0 | 3 | |
| titanium (Ti) | 0,1 | 3 | |
| zinc (Zn) | 1, 0 | 3 | |
| 11.31. Aluminum alloys | |||
| Deformable | aluminum (Al) | 0,5 | 2 |
| manganese (Mn) | 0,1 | 3 | |
| iron (Fe) | 0,3 | ||
| copper (Cu) | 1, 0 | 3 | |
| zinc (Zn) | 1, 0 | 3 | |
| titanium (Ti) | 0,1 | 3 | |
| vanadium(V) | 0,1 | 3 | |
| foundry (GOST 2685) | aluminum (Al) | 0,5 | 2 |
| copper (Cu) | 1, 0 | 3 | |
| silicon (Si) | 10, 0 | 2 | |
| manganese (Mn) | 0,1 | 3 | |
| zinc (Zn) | 1, 0 | 3 | |
| titanium (Ti) | 0,1 | 3 |
Certification
The main document remains approved by the USSR Ministry of Health dated 7.VIII.79 No. 123−12.328−7 with the additions RTM 27−72−15−82 “Procedure for the use of metals, synthetic and other materials in contact with food products and environments.”
Finishing materials approved by the USSR Ministry of Health are still referred to by SNIP (sanitary norms and rules) for food industry enterprises. The rules provide for obtaining a hygienic certificate for the use of a specific alloy if the alloy complies with RTM 27−72−15−82.
How to burn an aluminum cable
What to do if you need to tile a counter or box? It is best to take aluminum sheets of grades A or AD, approved by GOST for the manufacture of pans, or apply for a certificate from the sanitary and epidemiological control.
Buy, price
Aluminum alloys offered by Elektrovek-Stal LLC meet the requirements of the state quality standard. A wide selection of products, comprehensive advice from our managers, affordable prices and timely delivery determine the face of our company. For wholesale purchases there is a flexible system of discounts. We are waiting for your orders
/table
Source: https://ssk2121.com/pischevoy-alyuminiy-marka-splava/
Use of aluminum alloys in the food industry
Aluminum is used quite actively in the food industry, as well as in everyday life. It is used to make dishes, all kinds of containers for liquids and mixtures, and to make machines and equipment for food production. For this, food-grade aluminum sheets are usually used.
This is due to the fact that aluminum alloys do not in any way affect the composition of products or components of cosmetics. All vitamins, nutrients, original properties and microelements are completely preserved. In addition, they are not capable of harming human health.
Moreover, in the food industry it is allowed to use only food-grade aluminum and its alloys of certain grades.
Metal alloys containing aluminum can also be used. All grades of this metal that are allowed to be used in the food industry must fully comply with GOST.
Advantages of food grade aluminum
Food grade aluminum has many advantages, among which are the following:
- Not subject to corrosion. Thanks to this, kitchen equipment and tools can remain in water for a long time without harm.
- Food grade aluminum does not deform when exposed to high temperatures.
- Despite its coming into contact with materials having organoleptic properties, there is no change in the properties of the products. All vitamins present in them are also preserved.
- Due to sufficient rigidity, the material does not deform during cooking.
- Food grade aluminum is absolutely harmless to the human body and completely hygienic.
- Dishes made from this material can be used for cooking in ovens and microwave ovens.
Aluminum alloys and GOST
Food grade aluminum, which is used for the production of cookware and other similar products, can be not only in its pure form, but also in the form of various alloys, each of which has international and state quality standards, which indicate how and for what purposes they can be used .
Grades of metal alloys, including aluminum
You can also use metal alloys that contain aluminum. These include brands AB, AVM, A0, AD1, AD1M, AL22, AL23, AMg22. All these alloys are actively used for making spoons.
Quite often, products made from food-grade aluminum or its alloys must subsequently have a special coating applied. But this can be done with the AMts brand, since its chemical composition fully complies with GOST.
Food grade aluminum has long been firmly established in our daily use. It is impossible to find a kitchen that does not have utensils made from this metal. Reviews about it are only positive, and, apparently, its popularity is not going to decline.
Source: https://monateka.com/article/27655/
Features of aluminum
- Light and soft, has a low melting point - about 650 degrees.
- It is not subject to corrosion - a thin film of aluminum oxide is formed on the Al surface, protecting it from destruction. Thanks to this, equipment and products made from sheet aluminum can be exposed to water for a long time without any consequences.
- It is not destroyed by most food acids and alkalis.
- Very plastic. This property allows it to be rolled into very thin foil.
- High thermal and electrical conductivity with a low coefficient of heat capacity determines the absence of deformation when exposed to high and low temperatures and the preservation of high rigidity of products.
- It does not affect the composition of products and components in contact with the surface, which helps preserve the nutritional and beneficial properties of products, vitamins and original microelements.
- Not harmful to health.
- Easy to manufacture, post-process and subsequently use – it polishes, pours, molds, and also cleans and washes well.
Scope of application
- Making dishes.
- Production of containers for storing liquids and mixtures, including canned food and tubes.
- Production of packaging for transportation and storage of food products.
- Production of packaging for cosmetics.
- Production of heat-resistant products, including frying surfaces.
- Manufacturing of machines and molds for the food industry.
- Electrical engineering (stranded wires, cables, transformer windings).
- Making foil.
- Cladding of workshops, storage areas, industrial refrigeration chambers.
- Aircraft construction (duralumin is used).
- Production of industrial, technical and household mirrors (using silumin).
- Aluminizing (coating steel parts with aluminum to impart anti-corrosion properties and protection against oxidation).
- Glassmaking.
Grades of food grade aluminum alloys and additional standards
According to GOST, food-grade aluminum must contain no more than a fixed amount of impurities of other substances: the proportion of lead should not exceed 0.15%, arsenic - 0.015%, zinc - 0.3%, beryllium - 0.05%.
According to GOST, the food industry requires the use of grade A5 aluminum (pure primary aluminum). Alloys such as Ak5M2, AK7, AK9, AK12 are also allowed for use. Other grades of food-grade aluminum can only be used with special permission. A separate GOST is provided for the manufacture of spoons. Also, if the manufacturing technology involves the subsequent application of a special coating, it is possible to use the AMts alloy (GOST 4784).
To summarize, it is worth paying attention to the fact that there are quite a few areas of application for food-grade aluminum sheets. The choice of this metal for production is determined by its technological characteristics, as well as its prevalence among natural resources and as a product on the world market.
Food-grade aluminum has undoubtedly proven itself to be a reliable material in everyday life and production, and its service to humanity will be appreciated more than once.
from here
Filed under aluminum
Source: https://tsvetmet.wordpress.com/2019/06/12/%D0%BF%D0%B8%D1%89%D0%B5%D0%B2%D0%BE%D0%B9-%D0% B0%D0%BB%D1%8E%D0%BC%D0%B8%D0%BD%D0%B8%D0%B9/
What to consider when purchasing aluminum sheet: types of material, prices and suppliers
Aluminum sheet is one of the most popular materials in industry and private construction. There are several types of aluminum sheets, differing in processing method, size and cost. What is cold-worked and clad sheet, what kind of corrugations are there, and what should you pay attention to when choosing and purchasing aluminum sheet?
What types of aluminum sheets are there?
Aluminum sheet is a semi-finished product made from aluminum or its alloys with the addition of other metals by hot deformation and subsequent cold rolling. Its main characteristics: high anti-corrosion properties, ease of machining, low weight, ductility and resistance to low temperatures. All this allows aluminum sheet to adequately compete with rolled stainless steel, and in some ways even surpass it.
Sheet aluminum is supplied to consumers in sheets of measured length, multiples of measured length within the lengths established by GOST 21631-76 (with an interval of 500 mm), unmeasured lengths or in rolls weighing from one to three tons. Depending on the grade of aluminum and its processing technology, the length of the sheet ranges from 2000 mm to 7000 mm.
Width of aluminum sheet in mm, established by GOST: 600, 800, 900, 1000, 1200, 1400, 1600, 1800, 2000.
In terms of sheet thickness, sheet aluminum occupies an intermediate position between aluminum foil (thickness 0.007–0.2 mm) and aluminum plates (thickness 11–200 mm). GOST 21631-76 regulates both the actual thickness of the aluminum sheet and the maximum permissible deviations from it. According to GOST, the thickness of the aluminum sheet should be 0.3–10.5 mm.
Stamps
Aluminum sheets differ not only in size, but also in composition, processing method and shape. Among the most common grades of aluminum sheet, two types can be distinguished.
- Sheets produced from primary aluminum grade A0 (aluminum content 99%, hardness 25 MPa), A5 (99.5%, 20 MPa), A6 (99.6%, 20 MPa), A7 (99.7%, 20 MPa ). Primary aluminum is completely non-toxic and can be used in the food industry.
- Sheets made of technical aluminum grades AD and aluminum alloys with copper, manganese, zinc and magnesium grades AMg2nr, AMg3, AMg5, AMts, VD1, D16, D16A. They are used in various industries, such as shipbuilding, construction, mechanical engineering, and aircraft manufacturing.
The marking of sheet aluminum also indicates the manufacturing method, type of material processing and surface finishing, and sheet dimensions. For example, the marking of an aluminum sheet made of AD1 alloy, without heat treatment, conventional surface finishing, 1000 mm wide and 2000 mm long, will look like this: AD1-5x100x2000 GOST 21631-76.
In addition to GOST 21631-76, in accordance with which sheet aluminum for general and special technical purposes is manufactured, there are GOSTs for the chemical composition of individual grades:
- GOST 11069-74 - regulates the chemical composition of grade A5;
- GOST 1131-76 - chemical composition of grade VD1;
- GOST 4784-97 - chemical composition of rolled sheets of technical grades of aluminum.
Production
In accordance with GOST 21631-76, aluminum sheets are produced in one of two ways - hot or cold rolling. The cold rolling method can be used to produce aluminum sheets with a thickness of less than 6 mm. Thicker sheets are produced on a hot rolling mill.
In some cases, the sheet is coated with an additional layer of aluminum, copper and steel. This process is called cladding. Unclad sheets are made from primary or technical aluminum, which is highly resistant to corrosion. There are two types of cladding:
- Normal plating. The sheet is made from durable and hard aluminum alloys that require anti-corrosion protection. When the sheet thickness is more than 1.9 mm, a layer of aluminum with a thickness of 2% of the thickness of the sheet itself is used for cladding. For thinner sheets, the cladding layer is at least 4%. In the marking it is indicated by the letter “A”.
- Technological cladding (B). In this case, the cladding layer is 1.5% of the sheet thickness and is applied only to facilitate the rolling process and improve the appearance of the sheet.
Important!
For use in aggressive environments, it is necessary to choose an unclad aluminum sheet or a sheet with normal cladding. Technological plating cannot protect against corrosion.
Material processing
To give aluminum sheets additional qualities, they are subjected to thermal or mechanical treatment. As a result, the sheets change their physical properties and become more malleable and ductile. According to the processing method, aluminum sheets are divided into several types:
- Aluminum sheet without heat treatment. It is obtained by cold working. This sheet has sufficient strength due to its thickness of 5–10.5 mm.
- Annealed aluminum sheet. Annealing is heating a material to a certain temperature, followed by holding and slow cooling. Processing sheets by annealing helps relieve internal stresses in the metal, improve its quality and improve machinability. The letter “M” is used to mark such sheets.
- Cold-worked aluminum sheet. Cold hardening is the cold processing of aluminum by pressure. This method effectively increases the strength and hardness of the sheet. A cold-worked sheet 2 mm thick has a tensile strength twice as high as an annealed sheet of the same thickness and grade. Cold-worked sheets are marked with the letter “H”.
- Hard-worked to one-half or half-hard-worked (H2).
- Refined aluminum sheet (P). For its production, aluminum is used, purified by electrolysis from non-metallic inclusions and gases.
- Hardened aluminum sheet. Hardening is a thermal processing method similar to annealing, but differs from the latter in the rapid cooling of the material. When hardening, the wear resistance of the sheet and its strength significantly increase.
- Naturally aged aluminum sheet. With this method, the sheets are aged at room temperatures for a certain time. Natural aging is used mainly to strengthen sheets of aluminum alloys.
The surface finish of the sheet can be normal (without special markings), high (P) and high (H). According to GOST 21631-76, high-finish sheets are made from aluminum grades A6, A7, A5, A0, AD and some alloys. The thickness of the sheet with high finishing is up to 4 mm.
Leaf shape
Aluminum sheets are divided into several types according to their shape:
- sheets of general and special purpose (standard);
- corrugated aluminum sheets;
- perforated sheets;
- corrugated sheets.
General purpose and specialty sheets have a smooth surface in a regular, raised or high finish. These sheets are mainly used in the production of stainless steel structures for the food, fuel, chemical industries and mechanical engineering. For the manufacture of sheets for general and special purposes, aluminum and its alloys of grades A5, AD, AMg1, AMg2, AMg3, AMg5, AMg6, A6M, AMts, AD1, VD1, D16 are used.
Corrugated aluminum sheets are a type of sheet with a rectangular cross-section and a convex pattern on the surface formed by so-called corrugations. The riffles are located at a certain angle to each other and can be of several types:
- “lentil” is the simplest pattern, consisting of one repeating riffle;
- “duet” - a pattern with double corrugation arranged in a checkerboard pattern;
- “quintet” is a pattern of five parallel riffles perpendicular to each other.
Source: https://www.kp.ru/guide/aljuminievyi-list.html
Grades of food grade aluminum according to GOST
Aluminum is a non-ferrous metal with low density. The surface of the alloy is silver-white, matte. It is very light and soft, due to which it has a low melting point - approximately 650 degrees. It has found its application in all spheres of human life. It is actively used in the food industry, including for the manufacture of various tableware. It ranks second in production among all metals in the world, after iron.
Aluminum is susceptible to the aggressive effects of acids. Able to dissolve in concentrated alkali solutions. To avoid such phenomena, all aluminum products are covered with protective films. In a crushed dusty state, being in an oxygen environment, it supports active combustion.
The thermal and electrical conductivity properties of this metal are comparable to gold, silver and copper. Very common in electrical engineering. Multicore wires and cables are made from it, and windings for electric motors and transformers are created.
Aluminum is very ductile, but very fragile. It can be rolled out to a translucent foil. Aluminum ingots can be easily planed and cut.
By introducing appropriate additives, the strength of the alloy can be significantly increased, thereby expanding the range of its applications.
A similar alloy was developed in 1911 by German craftsmen in the town of Düren. This is where the name of the alloy consisting of aluminum, copper, magnesium and manganese comes from - duralumin, or duralumin.
This combination and long-term hardening made it possible to increase the strength characteristics and maintain the same lightness (aluminum is 3 times lighter than steel). Duralumin alloy has found great use in aircraft construction, due to which it has been nicknamed “winged metal”.
To maintain anti-corrosion characteristics, it was coated with pure aluminum.
To eliminate such sputtering, another aluminum alloy with silicon inclusions was developed - silumin. Due to its shine and silvery color, aluminum is used in the production of mirrors, both industrial and technical (for example, for telescopes), and household ones.
Food grade aluminum - what is it?
- 1 Food grade aluminum alloy - Metalist's Handbook
- 2 Aluminum and aluminum alloys in the production of tableware and food equipment
- 3 Food grade aluminum
- 4 Aluminum scrap, types, description, prices
- 5 Aluminum alloys in the food industry. Buy food grade aluminum today. The best price for food-grade aluminum from the supplier - the Auremo company / Auremo
- 6 Food grade aluminum alloy - Metals, equipment, instructions
the modern food industry without aluminum . But not all products are regulated by GOST. Questions arise when it is necessary to line the inside of a container or box for food products, make a muffin tin, tray, or upholster a counter.
What kind of aluminum can be called food grade? For products made of aluminum or aluminum alloys, just open GOST.
What is the difference between aluminum, duralumin and food grade aluminum?
Aluminum is a light silver metal. It is light, relatively soft, and melts at a temperature of 660.4°C. Al easily dissolves in strong alkalis and is resistant to acids, since a protective film is formed on its surface. Finely crushed metal burns in air when heated. The smaller its particles, the lower the heating temperature is needed for combustion.
Aluminum has high thermal and electrical conductivity. This metal is very ductile. This property allows it to be rolled into very thin foil. It also has low strength: pure aluminum can be easily cut with a knife. This metal is very resistant to corrosion - a thin film is formed on the surface of Al, protecting it from destruction.
Depending on the amount of impurities - the purity of the metal - in accordance with GOST, aluminum is assigned a certain grade.
Duralumin – aluminum alloy
Duralumin was produced in 1909 in the city of Duren, Germany. The new chemical alloy, which was named after the city, quickly gained popularity throughout the planet. The approximate composition of duralumin is: 94% aluminum, 4% copper, 0.5% each of manganese, magnesium, iron and silicon. The alloy is heated to 500°C, then quenched in water and subjected to natural or artificial aging.
The most common aluminum alloy today is duralumin. After hardening, duralumin acquires special hardness and becomes approximately seven times stronger than pure aluminum.
It, however, remains light - almost three times lighter than iron. The alloy has become much stronger, but has lost one of its most important properties—corrosion resistance. Again we had to use aluminum to combat corrosion.
Items made of duralumin began to be clad, i.e. cover with the thinnest layer of pure aluminum.
Aluminum in everyday life
In everyday life, so-called food grade aluminum is used. According to GOST, food grade aluminum must contain very small amounts of lead, zinc and beryllium impurities. It is also resistant to corrosion, as a dense oxide film forms on its surface. Aluminum is used very widely for household purposes. Spoons, forks, pots, basins and other utensils are made from it. Toothpaste, sauces, seasonings, and canned food are produced in tubes.
Why is food grade aluminum so often used in the food industry? This metal is not prone to corrosion, so dishes and kitchen appliances can withstand long-term contact with water.
When storing food in contact with this metal, smells and tastes do not change, and vitamins are not destroyed during the cooking process. Aluminum conducts heat very well, thereby speeding up the cooking process. This metal has sufficient rigidity - it does not deform during the cooking process.
In addition, it can be used in ovens and microwaves. Food grade aluminum is an absolutely harmless material.
Food foil has also found very wide application. But foil is thinly rolled aluminum with a thickness of 0.009 to 0.2 mm. This is an excellent packaging material. In the confectionery industry, cookies, candies and ice cream are wrapped in it. Foil wrappers are used to package butter and margarine.
Due to its ability to conserve heat, foil is used for storing and transporting food. Moreover, during the process of bending and folding, the integrity of the foil is not compromised.
The resulting food packaging has become popular not only because of its strength and flexibility. Aluminum foil is very resistant to external influences: foreign odors, high humidity. It does not interact with the food itself or with its smell, that is, it does not change them.
Source: https://www.kakprosto.ru/kak-830839-chem-otlichayutsya-alyuminiy-dyuralyuminiy-i-pischevoy-alyuminiy
