Tempering temperature min 425℃
Tensile Nom 900MPa
Tensile min 900MPa
Yield strength Nom 720MPa
Yield strength min 720MPa
Proof load Nom 650MPa
Elongation after fracture of machined test pieces min 10%
Percentage reduction of area after fracture, Machined test pieces min 48%
Vickers hardness F no less than 38N min 290HV
Vickers hardness F no less than 38N max 360HV
Brinell hardness F=30D^2 min 286HB
Brinell hardness F=30D^2 max 355HB
Rockwell hardness min 37HRC
Rockwell hardness max 当采用HV0.3测定表面硬度及芯部硬度时,紧固件表面硬度不应比芯部硬度高出30HVHRC
Surface hardness and Core hardness HV0.3 28
Hardness decrease of retempering max 20HV