SUS440A
● Features and application:
       SUS440A stainless steel hardened state, the hard, but better than 440B, 11Cr17 toughness. Used as cutting tools, measuring tools, bearings.
● Chemical Composition:
       Carbon C: 0.60 ~ 0.75
       Si Si: ≤ 1.00
       Manganese Mn: ≤ 1.00
       Sulfur S: ≤ 0.030
       Phosphorus P: ≤ 0.035
       Chromium Cr: 16.00 ~ 18.00
       Ni: to allow containing ≤ 0.60
       Mo Mo: ≤ 0.75 can be added
● Mechanical Properties:
       Hardness: Annealed, ≤ 255HB; quenching and tempering, ≥ 54HV
● Heat treatment and microstructure specifications:
   Heat treatment specifications:
     1) annealing, 800 ~ 920 ℃ slow cooling; 2) quenching, 1010 ~ 1070 ℃ oil cooling; 3) temper, 100 ~ 180 ℃ fast-cooling.
   Microstructure:
     Organizing for the martensitic type.
● Delivery status:
     Generally heat treatment delivery, the treatment types specified in the contract; not indicated, according to the heat treatment state of delivery.