STUDY THE EFFECT OF HEAT TREATMENT TO MECHANICAL PROPERTIES FOR ALLOW ALLOY CASTING STEEL

Abstract

In this research the degree of starting the end of transformation for phases have been identified in different averages levels of heating and cooling and calculated the transformation time in each case by using device of Dilatometer for casting steel DIN 1.2067. The behaviors of fatigue strength, tension strength, impact strength and hardness strength have been studied for four selection groups one of them casting and other three have been heated treatment such as quenching in water, quenching in water and tempering at 260 oC, quenching in water and tempering at 620 oC. These tests carried out by affecting of constant stress capacity for standard samples have cylindrical shape by using the rotating bending with stress ratio is (R= -1) and standard samples for testing tension strength and impact strength. The results have been shown that the heat treatments lead to improve fatigue strength, fracture stress, yield point, impact strength, hardness and the best was quenching in water and tempering at 260 oC.