中频淬火曲轴磨削裂纹产生原因及对策

The Causes and Countermeasures of Grinding Crack of Intermediate Frequency Quenching Crankshaft

磨削表面烧伤是磨削过程的瞬时高温使工件金属表面产生一层很薄的氧化层,对于已淬硬件来说可能会造成表面磨削回火软化,严重的甚至产生裂纹,影响工件的耐磨性和使用寿命。以某型号发动机的球墨铸铁曲轴中频淬火后在磨削加工时轴颈表面产生裂纹现象为实例,分析轴颈表面由于磨削烧伤而产生裂纹的原因,并从热处理工艺及磨削工艺两个方面介绍了消除磨削裂纹的方法。

The surface grinding burn is what the metal surface of the work piece creates a very thin oxide with the instantaneous high temperature in grinding process. This may cause the surface grinding temper softening to the work piece of quenching hardware, serious and even crack, impact wear resistance and service life of the work piece. Based on the shaft neck surface crack of nodular cast iron crankshaft of a certain type of engine when grinding after medium frequency quenching as an example, the reason of grinding burn and cracks on the shaft neck surface was studied and analyzed, and the method to eliminate grinding cracks was introduced from two aspects of the heat treatment process and grinding process.