Overview
UNS S44003, also known as AISI 440B, is a high-carbon martensitic stainless steel that offers a balance of strength, hardness, and corrosion resistance. This alloy is part of the 440 series, positioned between 440A and 440C in terms of carbon content and properties.
Typical Uses
Valve components, pump parts, and bearings.
MetalTek Grade
MTEK 440B
Poured At:
Carondelet Division, Sandusky International Division, Wisconsin Centrifugal Division, Wisconsin Investcast Division
Similar Specifications
Wrought UNS: S44003
Wrought Grade: 440B
Typical Chemical Composition (% by wt.)
Aluminum: n/a
Carbon: 0.75-0.95
Chromium: 16-18
Manganese: 1
Iron: BAL
Copper: n/a
Nickel: n/a
Lead: n/a
Tin: n/a
Silicon: 1
Zinc: n/a
Other: Mo 0.75
Minimum Mechanical Properties
Heat Treatment: Anneal
NOTES: Brinell value is MAX.
Frequently Asked Questions
Martensitic steel is a magnetic stainless steel that is heat-treatable and used for applications requiring high hardness.
Martensitic steel is used in chemical and food processing equipment, impellers, turbine engine components, and wear-resistant parts where hardness and strength are critical.
Austenitic steel is non-magnetic, corrosion-resistant, and ductile. Martensitic steel is magnetic, harder, heat-treatable, and more wear-resistant but less corrosion-resistant.
Martensitic steel offers high hardness, wear resistance, and strength after heat treatment, ideal for demanding mechanical applications.
Yes, martensitic steel can be heat treated through quenching and tempering to increase hardness and mechanical performance.
Yes, martensitic stainless steel is magnetic due to its body-centered tetragonal (BCT) structure after quenching.