According to ISO 898-1, Mechanical pr physical property for class 12.9 is as below:

Tensile strength min 1220 MPa

Stress at 0.2% non-proportional elongation, Rp0.2, min 1100 MPa

Stress under proof load, 970MPa

percentage elongation of area after fracture for machined test pieces, A,  8%

Percentage reduction of area after fracturer for machined test piece, Z,  44%

Vickers hardness, HV, 385 ~ 435

Surface hardness, HV0.3, 435

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