Steel Solutions since 1982

Peeled Round Bars / Stainless Steel

AISI 440C

High Carbon Martensitic Stainless Steel

Material Overview

AISI 440C - High Carbon Martensitic Stainless Steel

Material Type

Type: Martensitic, heat-treatable stainless steel

Key Benefit: Highest hardness among all stainless steels

Mechanical Properties

Hardness (Heat Treated): 55-60 HRC
Wear Resistance: Very High
Corrosion Resistance: Moderate

Corrosion & Wear Resistance

  • Wear Resistance: Exceptional - suitable for cutting and bearing applications
  • Corrosion Resistance: Moderate - better than carbon steel, less than 304/316
  • Edge Retention: Excellent for cutting tools

Applications

  • High-precision ball bearings and roller bearings
  • Knife blades and cutting tools
  • Valve components and seats
  • Dies and punches
  • Surgical instruments
  • Measuring instruments and gauges
  • Nozzles and wear plates

Advantages

  • Maximum Hardness: Highest among stainless steels
  • Wear Resistance: Exceptional abrasion resistance
  • Edge Retention: Maintains sharp edges
  • Corrosion + Hardness: Unique combination of properties

Heat Treatment

  • Hardening: Austenitize at 1010-1065°C, quench in oil or air
  • Tempering: 150-370°C for desired hardness
  • Annealing: 870-900°C for softening
  • Stress Relief: Recommended after machining

Processing Characteristics

  • Machinability: Fair - best machined in annealed condition
  • Grinding: Excellent finish achievable
  • Welding: Not recommended - prone to cracking
  • Polishing: Takes excellent mirror finish