UNS S44003 Martensitic Stainless Steel – Enhanced Wear-Resistant Alloy

Description

UNS S44003 is the medium-carbon variant in the S44000 series (AISI 440B), positioned between S44002 and S44004 in terms of carbon content (0.75-0.95%) and performance. It retains the 16.0-18.0% chromium content of the series, plus 0.75-1.25% molybdenum to enhance wear resistance and pitting protection compared to S44002. Its martensitic structure ensures magnetic properties, and it can be heat-treated to achieve higher hardness than S44002, while remaining more formable than S44004. Unlike S44002, S44003 offers a step up in wear resistance, making it suitable for applications where durability is a priority but processability is still needed. It performs well in dry or slightly corrosive conditions, making it ideal for high-performance industrial components.

Chemical Composition (wt%)

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

Mechanical Properties

Tensile Strength ≥ 860 MPa, Yield Strength ≥ 620 MPa, Elongation ≥ 8%, Hardness ≤ 285 HB (annealed); Tensile Strength ≥ 1250 MPa, Yield Strength ≥ 960 MPa, Elongation ≥ 6%, Hardness 56-60 HRC (heat-treated)

Advantages

Higher wear resistance than S44002; molybdenum-enhanced pitting resistance; heat-treatable to high hardness; magnetic; balanced processability (formability/weldability) between S44002 and S44004; good corrosion resistance in mild environments.

Applications

High-performance blades, knives, bearings, valves, gears, pump parts, and industrial components requiring enhanced wear resistance compared to S44002.

Equivalent Grades

AISI 440B, EN 1.4125, GB 8Cr17, 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.