ASTM 440C Stainless Steel

 

1.Core Chemical Composition (Typical, wt%)

Chromium (Cr): 16.0–18.0%

Carbon (C): 0.95–1.20%

Molybdenum (Mo): 0.75–1.25%

Manganese (Mn): ≤1.00%

Silicon (Si): ≤1.00%

Phosphorus (P): ≤0.040%

Sulfur (S): ≤0.030%

Iron (Fe): Balance

2. Key Mechanical Properties (After Heat Treatment)

Hardness: Up to 58–62 HRC (achieved by quenching and tempering)

Tensile Strength: ≥1790 MPa

Yield Strength: ≥1480 MPa

Elongation: ≥10%

3. Main Characteristics

Outstanding Hardness & Wear Resistance: Its high carbon content enables it to reach a very high hardness after heat treatment, making it suitable for cutting tools and bearing components.

Moderate Corrosion Resistance: Better than most carbon steels, but lower than austenitic grades like 304/316. It resists mild corrosion in dry environments but is prone to rust in humid or salty conditions.