GB/T6402-2008 / SEP921-84. ASTM A388
HEAT TREATMENT SPECIFICATION & MECHANICAL PROPERTIES:
Tenlise strength ≥966N/mm2 yeild strength ≥793N/mm2
Elongation ≥13% reduction of area ≥45%
Impact test v notch, radial direction ≥55J(20℃)
Hardness :
285-341HB
Grain size (ASTM112) ≥5 or fine .
Non-metallic inclusion as per ASTM-45 method A:
A B C D ≤2.5 ≤2.0 ≤1.5 ≤2.0
DELIVERY CONDITION : as per drawing.