CARBIDES IN STEEL 4335 V

Three types of alloy carbides have been observed in tempered steel 4335V:M_3C,M_7C_3 andM_4C_3.The precipitation temperatures are 200—700,400 and 500 ℃ respectively.The com-position,morphologies and distribution patterns of the carbides as well as the relationship be-tween them and as-quenched substructures have been investigated.The influence of the car-bides on the low temperature impact toughness of the steel has also been discussed.