SUS440B
Features and application:
     SUS440B stainless steel than SUS440A high hardness, high toughness steel than SUS440C. SUS440B for cutting tools, measuring tools and bearings. Chemical composition:
        SUS440B carbon (C) 0.85 ~ 0.95, manganese (Mn) ≤ 0.80, Nickel (Ni) ≤ 0.60, silicon (Si) ≤ 0.80, phosphorus (P) ≤ 0.035, sulfur (S) ≤ 0.030, chromium (Cr) 17.00 ~ 19.00, molybdenum (Mo) 1.00 ~ 1.30 Ni: to allow containing ≤ 0.60
Mechanical properties:
        Hardness: Annealed, ≤ 255HB; quenching and tempering, ≥ 56HV
Heat treatment and microstructure specifications:
        Heat treatment specifications:
          1) annealing, 800 ~ 920 ℃ slow cooling;
          2) quenching, 1010 ~ 1070 ℃ oil cooling;
          3) tempering, 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.