碳钢件表面裂纹缺陷激光修复研究

Study on the Laser Repairing Surface Crack of Steel Components

采用双光束激光修复碳钢零件的表面裂纹。裂纹修复区堆焊层与零件基体间存在一明显的白色熔合结合带 ,组织结构中存在联生的胞晶组织及树枝状、针状组织。枝晶为先析出相γ Ni,固溶有大量的Cu和Fe ;枝晶间隙除低熔点金属外 ,含有γ Ni,NiSi2 ,Cr3 Ni2 ,CrSi。修复区送料堆焊层的硬度明显高于碳钢基体的硬度 ,约在HV0 .2 40 0～HV0 .2 45 0 。

Surface crack of steel components was repaired with two bundle of laser. There was an obvious joined band between filled region and substrate of component. The microstructure of repaired region were adnate cellular crystal, dendrite crystal, and needleshaped crystal. The phases of dendrite crystal in repaired region were consisted of γ-Ni which contained plenty of Cu, Fe. The phases in the gaps among dendrite crystals were γ-Ni, NiSi2, Cr3Ni2, CrSi. The hardness of filled layer in repaired region were HV0.2400-HV0.2450, then the hardness values decreased from the surface to transition region.