Zhejiang Deqing Steel Market Co.,Ltd

Steel 420 is a martensitic stainless steel known for its ability to achieve high hardness through heat treatment. It is also called 420 stainless steel, AISI 420 steel, UNS S42000, 420 steel, or 420 stainless in different markets. Compared with austenitic stainless grades, steel 420 is chosen when hardness, wear resistance, machinability, polishability, and mechanical strength are more important than maximum corrosion resistance.
Zhejiang Deqing International Steel Market supports steel 420 sourcing for tool makers, mold factories, machining workshops, valve manufacturers, pump component producers, blade manufacturers, industrial equipment suppliers, importers, distributors, and project buyers. Available forms include 420 stainless steel plate, 420 stainless steel sheet, 420 stainless steel bar, 420 round bar, 420 flat bar, 420 stainless steel coil, 420 stainless steel strip, and 420 stainless steel pipe. Buyers can confirm standard, size, tolerance, surface finish, heat treatment condition, cutting request, inspection requirement, packing method, and delivery schedule before order arrangement.
The main feature of steel 420 is heat treatability. In an annealed condition, 420 stainless steel is easier to machine and prepare for forming or component production. After quenching and tempering, AISI 420 steel can reach higher hardness, making it suitable for knives, blades, molds, dies, measuring tools, surgical instruments, shafts, fasteners, valve parts, pump parts, bearings, wear plates, and mechanical components. The final hardness of steel 420 depends on heat treatment process, section size, cooling method, and tempering temperature.
Corrosion resistance should be understood correctly. Steel 420 contains chromium, so it provides better corrosion resistance than plain carbon steel in many mild environments. However, 420 stainless steel is not usually selected for highly corrosive chloride, marine, or strong chemical conditions. For better performance, the surface of 420 steel should be polished, cleaned, passivated when required, and kept away from long-term deposits or trapped moisture.
Product selection depends on the final application. 420 stainless steel plate is used for molds, wear parts, tooling plates, machine components, and industrial cutting parts. 420 stainless steel sheet supports thin blades, covers, precision parts, and polished components. 420 stainless steel bar and 420 round bar are used for shafts, pins, fasteners, valves, fittings, and machined parts. 420 stainless steel coil and 420 stainless steel strip support stamping, forming, blades, springs, and continuous production.
When purchasing steel 420, buyers should not compare only price. Important details include chemical composition, hardness target, annealed or hardened condition, straightness, flatness, thickness tolerance, diameter tolerance, surface finish, machining allowance, heat treatment requirement, testing request, and packing protection. Correct steel 420 selection helps improve wear resistance, reduce machining problems, control rework, and support stable service life.