Grade 440B Stainless Steel – Medium-Carbon 440 Variant For Enhanced Wear Resistance

Overview

Grade 440B is the medium-carbon variant of the 440 family, offering higher wear resistance than 440A while maintaining good toughness. It contains 0.75-0.95% carbon and 16.0-18.0% chromium, with molybdenum addition to improve corrosion resistance and hardenability. Unlike 440A, Grade 440B achieves higher hardness after heat treatment (up to 58 HRC), making it suitable for applications requiring increased wear resistance. It is magnetic and has good machinability when annealed, though it requires more careful heat treatment than 440A to avoid brittleness.

Chemical Composition (wt%)

C: 0.75-0.95, Cr: 16.00-18.00, Mo: 0.75-1.25, Mn ≤ 1.00, Si ≤ 1.00, P ≤ 0.045, S ≤ 0.030, Ni ≤ 0.75

Typical Mechanical Properties (Annealed Condition)

Tensile Strength (Rm): ≥ 700 MPa; Yield Strength (Rp0.2): ≥ 450 MPa; Elongation (A): ≥ 12%; Brinell Hardness (HB): ≤ 255

Core Advantages

Higher wear resistance than 440A; good toughness and corrosion resistance; heat-treatable to high hardness; magnetic; good machinability in annealed state; excellent edge retention for heavy-duty cutting tools.

Applications

Heavy-duty knives, bearings, gears, valves, and precision components requiring enhanced wear resistance and moderate corrosion protection.

Equivalent Grades

EN 1.4125, UNS S44003, GB 9Cr18Mo, SUS440B

Stainless Steel Suppliers

If you have project requirements for stainless steel, we welcome your order. GNEE has a large inventory of popular products for you to choose from. It can be processed into various practical product forms, including plates, coils, tubes, bars, wires, etc. For detailed chemical composition information and free samples, please contact our factory immediately. We offer competitive prices and excellent service.Email: info@gneestainless.com

 

Testing and Documentation: Factory test certificate, EN 10204 3.1, chemical report, mechanical report, destructive testing report, non-destructive testing report, PMI test report, visual inspection report, third-party inspection report, NABL certified laboratory report.
Packaging: Wooden crate packaging, bubble wrap packaging, steel strapping, or packaging according to customer requirements.