40Cr激光相变硬化工艺的研究

Experiments study on the 40Cr material's phase transformation harden by the laser

通过高能量的激光束处理工件表面进行激光相变硬化，使其达到所要求的硬化指标．由实验得出：随着激光输出功率的增大，工件硬化层深度和宽度有所增加，但增大到一定程度，工件表面由于温度高而熔融，硬化指标降低；随着激光扫描速度的增大，硬化层深度、宽度有所减小，但扫描速度降低，工件表面热影响区增大．硬化层组织在回火区由硬度较小的回火马氏体、回火索氏体组成，二次淬火区由硬度较大的超细化马氏体组成．

The laser phase transformation hardening is processed to obtain requirement hardening index of layer. On basis of experiments, it is found that the width and depth of the text reference blokes' hardening layer increased with the laser inlet power, as the power exceeded a limitation, the hardening index wound decreased because of molten. The width and depth decreased with the laser sweeping speed, but the lower velocity, the more thermal influence. The layer was made up of tempering martensite and sorbite in tempering region,finest martensite in quenching region.