F51是美标双相不锈钢锻件牌号,标准为:ASTM A182 化学成分如下: C ≤0.030 Mn ≤2.0 Si ≤0.20 Cr 24.0~26.0 Mo 2.5~3.5 Ni 5.5~6.5 P ≤0.030 S ≤0.020 N 0.08~0.20