以汽车曲轴用45钢为试验材料,对热轧和调质两种状态的无塑性预变形和有0.2%塑性预变形的两组材料经过不同加热次数后的力学性能和膨胀系数进行了试验研究,探讨了加法再制造中多次加热对零部件基体材料性能的影响。结果表明: 无论是热轧态还是调质态,在有限的加热次数内其强度、塑性、显微组织及材料膨胀系数均无显著变化。因此可认为在有限的加热次数下加热次数对再制造坯件基体材料的性能影响可以忽略。加法再制造既未对原有材料造成新的损伤,也未改善基体材料的原有状况。

The influence of heating during remanufacture on the performance of matrix material was discussed. 45 steel which was generally used in automobile crankshaft was tested in the experiment. Mechanical properties and expansion coefficient were measured respectively on hot-rolled steel and slack quench steel with and without 0.2% plastic deformation. Results showed the strength,plastic property,metallurgical structure and expansion coefficient did not change a lot after multiple heat process in all specimens. So the influence of limited multiple heat process on the matrix material of remanufacture blank could be neglected. The adding remanufacture method made neither additional damage nor improvement on the original performance of the matrix material.