论文部分内容阅读
采用覆砂铁型生产了DA471型QT700-2球铁凸轮轴,其铸态显微组织由50%～85%的珠光体和球状石墨组成,球化率大于85%。论述了正火(雾冷和强风冷却)和回火温度对凸轮轴中显微组织和力学性能的影响。结果表明,正火加回火后凸轮轴的珠光体含量大于95%,抗拉强度和伸长率分别大于700MPa和3%。该凸轮轴已经大量使用。
The DA471 QT700-2 ductile iron camshaft was produced by coated sand iron. The as-cast microstructure consisted of 50% -85% pearlite and spherical graphite, and the nodularity was more than 85%. The effects of normalizing (fogging and strong wind cooling) and tempering temperature on the microstructure and mechanical properties of camshafts are discussed. The results show that the content of pearlite in camshaft after normalizing and tempering is more than 95% and the tensile strength and elongation are more than 700MPa and 3% respectively. This camshaft has been used extensively.