Aluminum alloy can obtain good mechanical properties, physical properties and corrosion resistance by heat treatment.
Cast aluminum alloys can be divided into aluminum-silicon alloy, aluminum-copper alloy, aluminum-magnesium alloy and aluminum-zinc alloy according to chemical composition.
I. Pure aluminum products
Pure aluminum can be divided into two categories: smelting products and pressure processed products. The former is represented by chemical composition Al, and the latter is represented by Chinese phonetic alphabet LG (aluminum, industrial).
Second, the pressure processing of aluminum alloy
Aluminum alloy pressure processing products are divided into seven categories: rust prevention (LF), hardness (LY), forging (LD), superhard (LC), cladding (LB), special (LT) and brazing (LQ). The states of commonly used aluminum alloy materials are annealing (M-annealing), hardening (Y) and hot rolling (R).
Third, aluminum material
Aluminum and aluminum alloys processed into certain shapes are collectively referred to as aluminum materials, including plates, strips, foils, tubes, rods, wires and shapes.
Fourth, casting aluminum alloy
Cast aluminum alloy (ZL) is divided into four categories according to the main elements other than aluminum, namely 100, 200, 300 and 400.
V. High-strength aluminum alloy
High-strength aluminum alloy refers to aluminum alloy whose tensile strength is more than 480 MPa, mainly including hard aluminum alloy, superhard aluminum alloy and casting alloy.
Six, the typical use of different brands of aluminum alloy
Use of alloy code
1050 Extrusion coils for food, chemical and brewing industries, all kinds of hoses, fireworks powder
1060 requires high corrosion resistance and formability, but not high strength, so chemical equipment is its typical use.
1 100 is used to process parts and components that need good formability and high corrosion resistance but do not require high strength, such as chemical products, food industry devices and storage containers, thin-plate processed parts, deep-drawing or spinning concave utensils, welded parts, heat exchangers, printed boards, nameplates and reflective appliances.
1 145 packaging and thermal insulation aluminum foil, heat exchanger
1 199 electrolytic capacitor foil, optical reflective deposited film
1350 wire, conductive stranded wire, bus bar and transformer strip
20 1 1 screws and machined products requiring good cutting performance.
20 14 is applied to the occasions requiring high strength and hardness (including high temperature). Aircraft heavy-duty, forgings, thick plates and extruded materials, wheels and structural components, first-stage fuel tanks of multi-stage rockets and spacecraft parts, truck frames and suspension system parts.
20 17 is the first 2XXX alloy to be used in industry. At present, its application scope is narrow, mainly including rivets, general mechanical parts, structural parts of structures and transportation vehicles, propellers and accessories.
2024 Aircraft structures, rivets, missile components, truck hubs, propeller components and other structural parts.
2036 automobile body sheet metal parts
Structural parts and weapon structural parts of 2048 aerospace vehicle
2 124 aerospace structural parts
22 18 Piston of Aircraft Engine and Diesel Engine, Cylinder Head of Aircraft Engine, Impeller of Jet Engine and Compressor Ring
22 19 space rocket welds oxidant tank, supersonic aircraft skin and structural parts, and the working temperature is -270~300 degrees Celsius. Good weldability, high fracture toughness and high stress corrosion cracking resistance in T8 state.
Covered electrode and filler solder of 23 19 alloy.
26 18 die forgings and free forgings. Piston and aero-engine parts
2A0 1 Structural rivet with working temperature less than or equal to 100℃.
2A02 Axial compressor blade of turbojet engine with working temperature of 200~300℃.
2A06 Aircraft structure with working temperature 150~250℃ and aircraft structure rivet with working temperature 125~250℃.
The strength of 2A 10 is higher than that of 2A0 1 alloy, and it is used to manufacture aircraft structural rivets with working temperature less than or equal to 100 degrees Celsius.
2A 1 1 Moderate strength structural parts, propeller blades, vehicles and building structural parts of aircraft. Medium strength bolts and rivets for aircraft
2A 12 Aircraft skins, partitions, ribs, spars, rivets, etc., structural parts of buildings and transportation vehicles.
2A 14 Free Forgings and Die Forgings with Complicated Shapes
2A 16 Spacecraft parts working at 250~300 degrees Celsius, welded containers and airtight cabins working at room temperature and high temperature.
2A 17 Aircraft parts with working temperature of 225~250℃.
2A50 Medium Strength Parts with Complicated Shapes
2A60 Aircraft engine compressor wheel, guide wheel, fan, impeller, etc.
2A70 aircraft skin, aircraft engine piston, guide wheel, wheel disc, etc.
2A80 aero-engine compressor blades, impellers, pistons, expansion rings and other parts with high working temperature.
2A90 aero-engine piston
3003 is used to process parts and components that need good formability, high corrosion resistance and good weldability, or work that requires both these properties and higher strength than 1XXX alloy, such as kitchen utensils, food and chemical products processing and storage devices, tanks and tanks for transporting liquid products, and various pressure vessels and pipelines processed with thin plates.
The body of 3004 all-aluminum can requires parts with higher strength than 3003 alloy, chemical products production and storage devices, sheet metal processing parts, building processing parts, building tools and various lamp parts.
3 105 room partitions, baffles, prefabricated houses, gutters and downpipes, sheet forming parts, bottle caps, bottle stoppers, etc.
3A2 1 Aircraft fuel tank, oil conduit, rivet wire, etc. Building materials and food and other industrial equipment, etc.
Similar to 3003 alloy, 5005 has medium strength and good corrosion resistance. Used as conductor, cooker, dashboard, shell and architectural decoration. The anodic oxide film is brighter than the oxide film on 3003 alloy, and is in harmony with the color tone of 6063 alloy.
5050 sheet can be used as the inner lining of refrigerator and refrigerator, automobile air pipe, oil pipe and agricultural irrigation pipe; It can also process thick plates, pipes, bars, special-shaped materials and wires.
5052 This alloy has good formability, corrosion resistance, candling, fatigue strength and moderate static strength, and is used to manufacture aircraft fuel tanks and oil pipes, as well as sheet metal parts of traffic vehicles and ships, instruments, street lamp brackets and rivets, hardware products, etc.
5056 magnesium alloy and cable sheath rivets, zippers, nails, etc. Aluminum-clad wires are widely used in processing agricultural insect traps and other occasions where high corrosion resistance is needed.
5083 is used in places that need high corrosion resistance, good weldability and medium strength, such as welding parts of ships, automobiles and aircraft plates; Pressure vessels, refrigeration devices, TV towers, drilling equipment, transportation equipment, missile components, armor, etc. that need strict fire protection.
5086 is used in places that need high corrosion resistance, good weldability and medium strength, such as ships, automobiles, airplanes, cryogenic equipment, TV towers, drilling rigs, transportation equipment, missile parts and decks, etc.
5 154 Welded structures, storage tanks, pressure vessels, ship structures and offshore facilities, and transport tanks
5 182 sheet is used to process cans, automobile body panels, steering wheels, reinforcements, brackets and other parts.
5252 is used to manufacture decorative parts with high strength, such as decorative parts of automobiles. Having a bright and transparent oxide film after anodic oxidation.
5254 containers for hydrogen peroxide and other chemical products
5356 Welding aluminum-magnesium alloy covered electrode and welding wire with magnesium content greater than 3%
5454 welded structures, pressure vessels, and pipelines of offshore facilities.
5456 armor plate, high-strength welded structure, storage tank, pressure vessel and ship material.
5457 Decorative parts of automobiles and other equipment that have been polished and anodized.
5652 storage container for hydrogen peroxide and other chemical products
5657 Decorative parts of automobiles and other equipment that have been polished and anodized, but in any case, it is necessary to ensure that the materials have a fine grain structure.
5A02 Aircraft fuel tank and conduit, welding wire, rivet, ship structural parts.
5A03 medium strength welded structure, cold stamping parts, welding containers and welding wires can be used to replace 5A02 alloy.
5A05 welded structural parts, aircraft skin skeleton
5A06 welded structure, cold die forging parts, welded container stress parts, aircraft skin bone parts.
5A 12 welded structural parts, bulletproof deck
6005 extruded profiles and pipes are used for structural parts that require strength and height greater than 6063 alloy, such as ladders and TV antennas.
6009 automobile body panel
60 10 Sheet: Automobile Body
606 1 requires various industrial structures with certain strength, high weldability and corrosion resistance, such as pipes, rods, shapes and plates for manufacturing trucks, tower buildings, ships, trams, furniture, mechanical parts and precision machining.
6063 building profiles, irrigation pipes and extrusion materials for vehicles, benches, furniture and fences.
Extrusion material for 6066 forgings and welded structures
6070 heavy-duty welded structure and extrusion materials and pipes for automobile industry
6 10 1 Gong * * High-strength bars, electrical conductors and heat dissipation equipment for automobiles, etc.
6 15 1 is used for die forging crankshaft parts, machine parts and production of rolling rings, which requires good forgeability, high strength and good corrosion resistance.
620 1 high strength conductive bars and wires
6205 thick plate, pedal and high impact resistant extrusion parts
6262 requires threaded high-stress parts with corrosion resistance better than 20 1 1 and 20 17 alloys.
635 1 Extruded structural parts of vehicles, pipelines for water, oil, etc.
6463 profiles for buildings and various appliances, as well as automotive decorative parts with bright surfaces after anodic oxidation treatment.
6A02 Aircraft engine parts, forgings and die forgings with complex shapes.
7005 extrusion material is used to manufacture welded structures with high strength and fracture toughness, such as trusses, bars and containers of transportation vehicles; Large heat exchangers, and parts that cannot be treated by solid solution after welding; It can also be used to manufacture sports equipment such as tennis rackets and softball bats.
7039 Frozen containers, cryogenic instruments and storage boxes, fire-fighting pressure equipment, military equipment, armor plates and missile devices.
7049 is used for forging parts with the same static strength as that of 7079-T6 alloy, which require high stress corrosion cracking resistance, such as aircraft and missile parts-landing gear hydraulic cylinder and extrusion parts. The fatigue performance of the parts is roughly equal to that of 7075-T6 alloy, but the toughness is slightly higher.
Plate, extrusion, free forgings and die forgings for 7050 aircraft structural parts. The requirements of alloy for manufacturing this kind of parts are: high spalling corrosion resistance, stress corrosion cracking ability, fracture toughness and fatigue resistance.
Aluminum foil and ultra-thin strip of 7072 air conditioner; Cladding layers of 22 19, 3003, 3004, 5050, 5052, 5 154, 606 1, 7075, 7475, 7 178 alloy plates and pipes.
7075 is used to manufacture aircraft structures and futures. He requires high-stress structural parts and molds with high strength and strong corrosion resistance.
7 175 high-strength structure for forging aircraft. T736 material has good comprehensive properties, namely, high strength, spalling corrosion resistance, stress corrosion cracking resistance, fracture toughness and fatigue strength.
7 178 Parts requiring high compressive yield strength for manufacturing aerospace vehicles
Aluminum-clad and non-aluminum-clad plates, wing frames, stringers, etc. for 7475 fuselage. Other parts with high strength and fracture toughness.
7A04 aircraft skin, screws, and stressed components such as girders, frames, ribs, landing gear, etc.
State and code of wrought aluminum and aluminum alloy
1. range
This standard specifies the status code of deformed aluminum alloy.
This standard is applicable to aluminum and aluminum processed products.
2. Basic principles
2. 1 The basic status code is represented by an English capital letter.
2.2 Subdivision status codes are represented by basic status codes followed by one or more Arabic numerals.
2.3 basic status code
There are five basic states.
Description and application of code name
F Free machining state is applicable to products with special requirements for work hardening and heat treatment conditions during molding, and the mechanical properties of products in this state are not specified.
O Annealing state is suitable for the processed products with the lowest strength after complete annealing.
H Work-hardening state is suitable for products whose strength is improved by work hardening. After work hardening, the products may (or may not) undergo additional heat treatment to reduce their strength.
W solid solution heat treatment state treatment state is an unstable state, which is only applicable to alloys that are naturally aged at room temperature after solid solution heat treatment. This state code only indicates that the product is in the natural aging stage.
T Heat treatment state (different from F, O, H state) is suitable for stable products after heat treatment, with or without work hardening. T code must be followed by one or more Arabic numerals.
A kind of high alloy steel that can resist corrosion in air or chemical corrosive medium. Stainless steel is a kind of steel with beautiful surface and good corrosion resistance. It does not need surface treatment such as color plating, but exerts its inherent surface properties. It is used in many aspects, and is usually called stainless steel. High-alloy steels such as 13 chromium steel and 18-8 chromium-nickel steel represent the properties.
From the metallographic point of view, because stainless steel contains chromium, a very thin chromium film is formed on the surface, which is isolated from oxygen invading the steel and plays a role in corrosion resistance.
In order to maintain the inherent corrosion resistance of stainless steel, steel must contain more than 12% chromium.
304 is a universal stainless steel, which is widely used to make equipment and parts that require good comprehensive performance (corrosion resistance and formability).
304 stainless steel is a brand of stainless steel produced according to American ASTM standard. 304 is equivalent to 0Cr19Ni9 (0Cr18Ni9) stainless steel in China. 304 contains chromium 19% and nickel 9%.
304 is the most widely used stainless steel and heat-resistant steel. Used in food production equipment, chemical equipment, nuclear energy, etc.
Chemical composition of 304 stainless steel
Specification C Si Mn P S Cr Ni (nickel) Mo
SUS43 1 ≤0.08 ≤ 1.00 ≤2.00 ≤0.05 ≤0.03 18.00-20.00 8.25~ 10.50 -
304 is 1Cr 18Ni9.
The mechanism of stainless steel rust prevention is that alloy elements form a dense oxide film to isolate oxygen contact and prevent further oxidation. So stainless steel is not "stainless".
304 material rusts for the following reasons:
1. There are chloride ions in the use environment.
Chloride ion exists widely, such as salt, sweat, seawater, sea breeze, soil and so on. In the presence of chloride ion, stainless steel corrodes rapidly, even exceeding ordinary low carbon steel.
Therefore, there are requirements for the use environment of stainless steel, and it needs to be wiped frequently to remove dust and keep it clean and dry. (This will give him a "misuse". )
There is an example in the United States: an enterprise used an oak container to hold a solution containing chloride ions. The container has been used for nearly a hundred years, and it was planned to be replaced in the 1990s. Because the oak material was not modern enough and stainless steel was used, the container leaked due to corrosion 16 days after the replacement.
2. Without solid solution treatment.
The alloy elements are not dissolved into the matrix, which leads to low alloy content in the matrix and poor corrosion resistance.
3. This material without titanium and niobium has a natural tendency of intergranular corrosion.
Adding titanium and niobium and stabilizing treatment can reduce intergranular corrosion.
3 16 is a molybdenum-containing stainless steel. At high temperature, when the concentration of sulfuric acid is lower than15% and higher than 85%, 3 16 stainless steel has a wide range of applications. 3 16 stainless steel also has good chloride corrosion resistance.
The maximum carbon content of 3 16L stainless steel is 0.03, which can be used in applications where annealing after welding is impossible and maximum corrosion resistance is required.
corrosion resistance
The corrosion resistance is better than that of 304 stainless steel, and it has good corrosion resistance in the production of pulp and paper. Moreover, 3 16 stainless steel is also resistant to the corrosion of the ocean and corrosive industrial atmosphere.
heat resistance
3 16 stainless steel has good oxidation resistance in intermittent use below 1600 degrees and continuous use below 1700 degrees. In the range of 800- 1575 degrees, it is best not to continuously act on 3 16 stainless steel, but when 3 16 stainless steel is used continuously outside this temperature range, the stainless steel has good heat resistance. The carbide precipitation resistance of 3 16L stainless steel is better than that of 3 16 stainless steel, and the above temperature range can be used.
The difference between cold rolling and hot rolling;
Rolling at room temperature is generally understood as cold rolling. From the viewpoint of metallography, rolling below crystallization temperature is cold rolling.
Hot rolling, using slab (mainly continuous casting slab) as raw material, is made into strip steel by roughing mill and finishing mill after heating. The hot steel strip from the last finishing mill is cooled to the set temperature by laminar flow, and is coiled into a steel strip coil by a coiler. According to the different needs of users, the cooled steel strip coil is processed by different finishing lines (leveling, straightening, transverse cutting or longitudinal cutting, inspection, weighing, packaging and marking, etc.) to become steel plate, flat coil and longitudinal cutting steel strip products.
Cold rolling: The hot rolled steel coil is used as raw material, and then the scale is removed by pickling, and the finished product is a hard rolled coil. Because of the cold work hardening caused by continuous cold deformation, the strength and hardness of the hard rolled coil increase and the toughness and plasticity index decrease, so the stamping performance will deteriorate and it can only be used for parts with simple deformation. The hard rolled coil can be used as raw material for hot dip galvanizing plant, because all hot dip galvanizing units are equipped with annealing lines. The weight of hard rolled coil is generally 6~ 13.5 tons, and the hot-rolled pickling coil is continuously rolled at room temperature. The inner diameter is 6 10mm.
Product features: because it has not been annealed, its hardness is very high (HRB is greater than 90), and its machinability is very poor. It can only be simply bent at less than 90 degrees (perpendicular to the winding direction).
To put it simply, after a billet is heated (that is, the red and hot steel block burned on TV), it is rolled several times, then trimmed and corrected into a steel plate. This is called hot rolling.
Cold rolling is based on hot-rolled coil, which is generally a process of hot rolling-pickling-cold rolling. Cold rolling is made of hot rolled sheet at room temperature. Although rolling will also raise the temperature of the sheet during the processing, it is still called cold rolling.
Because of the continuous cold deformation from hot rolling, the mechanical properties are poor and the hardness is too high. It must be annealed to restore its mechanical properties, and those without annealing are called hard rolls.
Hard rolled coils are generally used to make products that do not need to be bent and stretched, and the lucky two-sided or four-sided bending with the thickness below 1.0.
The PH value of soy sauce is higher than that of vinegar, which is alkaline in the brewing process of soy sauce. 3 16L stainless steel is acid-resistant and alkali-resistant, which is the cause of decay.
There is no difference between the freshly cut rolled plate and the finished plate.
Finishing:
There are many kinds of aluminum alloys. . The density is different. Unable to write. It is divided into hard aluminum, forged aluminum, superhard aluminum and special aluminum alloys. Look for the above information.
304 stainless steel contains chromium 19% and nickel 9%, which is the most widely used stainless steel and heat-resistant steel. Used in food production equipment, chemical equipment, nuclear energy, etc.
The mechanism of stainless steel rust prevention is that alloy elements form a dense oxide film to isolate oxygen contact and prevent further oxidation. So stainless steel is not "stainless".
304 material rusts for the following reasons:
1. There are chloride ions in the use environment.
Chloride ion exists widely, such as salt, sweat, seawater, sea breeze, soil and so on. In the presence of chloride ion, stainless steel corrodes rapidly, even exceeding ordinary low carbon steel.
Therefore, there are requirements for the use environment of stainless steel, and it needs to be wiped frequently to remove dust and keep it clean and dry. (This will give him a "misuse". )
There is an example in the United States: an enterprise used an oak container to hold a solution containing chloride ions. The container has been used for nearly a hundred years, and it was planned to be replaced in the 1990s. Because the oak material was not modern enough and stainless steel was used, the container leaked due to corrosion 16 days after the replacement.
3 16 is a molybdenum-containing stainless steel. At high temperature, when the concentration of sulfuric acid is lower than15% and higher than 85%, 3 16 stainless steel has a wide range of applications. 3 16 stainless steel also has good chloride corrosion resistance.
The maximum carbon content of 3 16L stainless steel is 0.03, which can be used in applications where annealing after welding is impossible and maximum corrosion resistance is required.
corrosion resistance
The corrosion resistance is better than that of 304 stainless steel, and it has good corrosion resistance in the production of pulp and paper. Moreover, 3 16 stainless steel is also resistant to the corrosion of the ocean and corrosive industrial atmosphere.
heat resistance
3 16 stainless steel has good oxidation resistance in intermittent use below 1600 degrees and continuous use below 1700 degrees. In the range of 800- 1575 degrees, it is best not to continuously act on 3 16 stainless steel, but when 3 16 stainless steel is used continuously outside this temperature range, the stainless steel has good heat resistance. The carbide precipitation resistance of 3 16L stainless steel is better than that of 3 16 stainless steel, and the above temperature range can be used.