420 stainless steel sheet is Martensitic stainless steel. Its main components are iron, carbon, chromium, and a small amount of molybdenum, manganese, silicon, and other elements, usually containing between 0.15% and 0.40% of carbon, while containing 12% to 14% of chromium. Due to its high carbon content, 420 stainless steel has high hardness and strength, as well as good corrosion and wear resistance. It is therefore widely used in the manufacture of high-strength, high-hardness, and corrosion-resistant parts and equipment.
420 stainless steel sheets can be quenched and tempered to obtain different hardness and strength, and can also be cold-rolled or hot-rolled to obtain different dimensions and surface finishes, such as mirror, pickled and polished. Thus, it can be applied to various applications and process requirements.
-Cold Rolled 420 Stainless Steel Sheets
- Thickness: 0.3mm – 3.0mm
- Width: 600mm – 1500mm
- Length: 1000mm-6000mm
- Finish: 2B, BA, HL, NO.4, and so on
-Hot Rolled 420 Stainless Steel Plates
- Thickness: 3mm – 200mm
- Width: 600mm – 3200mm
- Length: 500mm – 12000mm
- Finish: Black, NO.1, Anneal pickling
Specification of 420 Stainless Steel Sheets And Plates
|420||Material Status||Y.S./Mpa ≥||T.S./Mpa ≥||E.L./% ≥||HB ≤||HRB ≤||HBW ≤||HV ≤|
|ASTM A240/A240M||Hardened and tempered||1470||1655||5||48||–||–||–|
|JIS G4304||Hardened and tempered||1320||1740||10||57||–||–||–|
|GB/T 1220||Hardened and tempered||1320||1740||10||57||–||–||–|
Note: The parameters are for reference only, and the specific parameters should also be based on the data provided by the actual manufacturer.
T.S. stands for tensile strength, Y.S. stands for yield, L. stands for elongation, HB stands for Brinell hardness, HRB stands for Rockwell hardness B, HBW stands for Brinell hardness W, and HV stands for Vickers hardness.
Different Performance in Different Material Status
420 stainless steel sheets will have some changes in performance in different material states, mainly in the following aspects:
Strength and Hardness: The strength and hardness of 420 stainless steel increase significantly after heat treatment, and the strength and hardness in the heat-treated state are much higher than in the cold-rolled state.
Toughness and Plasticity: The toughness and plasticity of 420 stainless steel will be improved after annealing, and the toughness and plasticity in the annealed state are higher than in the quenched state.
Corrosion Resistance: 420 stainless steel has different corrosion resistance in different states. In the heat treatment state, it is easy to produce chromium segregation at the grain boundaries, which affects its corrosion resistance. In the annealed state, the chromium is evenly distributed at the grain boundaries, so its corrosion resistance will be improved.
Processing Performance: The processing performance of 420 stainless steel in different states is also different. In the annealed state, 420 stainless steel has the best processing performance and is easily processed into various shapes; while in the quenched state, due to its higher hardness and strength, the processing difficulty also increases accordingly.
Production Process of 420 Stainless Steel Sheets And Plates
Melting and Casting
The raw material of 420 stainless steel is melted using electric, vacuum or gas-protected furnaces, and the molten steel is cast into a billet.
Hot Rolling or Forging
The billet is hot rolled or forged to make a blank with the desired shape and size.
Processing and Surface Treatment
The heat-treated billet is processed and surface treated to obtain the final 420 stainless steel product. Processing methods include cutting, cold drawing, cold rolling, polishing, grinding, etc.
The billet is heat treated to improve its mechanical properties and corrosion resistance. The usual heat treatment processes include solution treatment and aging treatment.
Features of 420 Stainless Steel Sheets And Plates
420 stainless steel sheets have excellent corrosion resistance, and can resist corrosion well in many chemical media.
420 stainless steel sheets are easy to process and shape, and can be processed in a variety of ways (such as cold processing, hot processing, machining, welding, etc.) to manufacture various shapes of parts and components.
420 stainless steel sheets can obtain high hardness and strength after quenching and tempering treatment. It also has good performance in grinding and wear resistance, which makes it suitable for manufacturing wear-resistant parts and tools, etc.
420 stainless steel sheets have stable performance in high-temperature environments, so it is widely used in equipment and machinery manufacturing for high-temperature work.
420 stainless steel sheets can be processed and formed to manufacture various shapes of parts and components with good plasticity.
Application of 420 Stainless Steel Sheets And Plates
Knife Manufacturing Industry
Because 420 stainless steel sheets have excellent hardness and wear resistance, it is often used in the production of various knives, such as scissors, saw blades, cutting blades, knife handles, etc.
Chemical Equipment Industry
420 stainless steel sheets have good corrosion resistance and high-temperature resistance, so it is often used in the manufacture of various chemical equipment, such as acid production equipment, salt production equipment, hydrogen chloride equipment, ammonia production equipment, etc.
Oil and Gas Extraction Industry
420 stainless steel sheets are commonly used in the manufacture of oil and gas extraction equipment, such as oil well casing, oil pipes, valves, pumps, etc. because it's corrosion resistance and high-temperature resistance can meet the harsh environmental requirements of oil and gas extraction.
Food Processing Industry
420 stainless steel sheets do not contain nickel and have good corrosion resistance and wear resistance, so it is often used in food processing equipment, such as food processing machinery, ovens, grills, etc.
420 stainless steel can be heat treated to improve its mechanical properties and corrosion resistance. Common heat treatments include annealing and quenching.
Annealing: By heating and holding, the grain size of 420 stainless steel is made larger to relieve stress and improve ductility. This is usually done at 840°C-900°C and then cooled to room temperature.
Quenching: By rapid cooling, the organization of 420 stainless steel undergoes phase transformation, thus improving its hardness and strength. Quenching can be divided into two ways, oil quenching and water quenching, and is usually carried out at about 1000°C.
It is important to note that parameters such as temperature, time and cooling rate need to be controlled during heat treatment to ensure that the desired mechanical properties and organization are obtained. Improper heat treatment may lead to degradation or failure of the properties of 420 stainless steel. Therefore, specific process requirements and standard specifications should be understood before heat treatment is performed.
304 and 420 stainless steel are two different stainless steel materials that have different chemical compositions and mechanical properties and therefore differ in their use and applications.
Chemical Composition: 304 stainless steel mainly contains elements such as chromium, nickel, and small amounts of carbon and manganese, while 420 stainless steel mainly contains chromium and a certain amount of carbon. Due to the difference in chemical composition, the two stainless sheets of steel have different properties in terms of corrosion resistance, strength, hardness, etc.
Mechanical Properties: 420 stainless steel is harder and more resistant to wear than 304 stainless steel, but its bendability and ductility are poor. 304 stainless steel, on the other hand, has better bendability and ductility and is usually used to manufacture products that require flexibility.
Application Areas: 304 stainless steel is widely used in kitchenware, decorative materials, chemical equipment, and medical devices, while 420 stainless steel is typically used to manufacture products that require high strength and hardness such as knives, bearings, and valves.
Although 420 stainless steel has high corrosion resistance, it is not incapable of rusting. Rusting may occur if 420 stainless steel is exposed to moisture, high temperatures, high oxidation or salinity for a long period of time.
In addition, the form of rusting of 420 stainless steel is different from other stainless steels, mainly because of its low chromium content, and pitting or halo-like rusting may occur. Therefore, when using 420 stainless steel products, care should be taken to avoid prolonged exposure to wet or corrosive environments in order to prolong its service life.
To minimize the risk of rusting of 420 stainless steel, surface treatment such as electroplating, polishing and painting can be applied to it. It is also very important to maintain and clean it regularly.