12CrNi3A钢凸轮轴的激光熔覆再制造技术

采用2 kW光纤激光器,在12CrNi3A钢制喷油泵凸轮磨损面获得了高硬度激光熔覆层,通过表面PT探伤、维氏硬度计、光学显微镜、摩擦磨损试验对熔覆层的完整性、硬度、显微组织及性能进行了表征。结果表明:熔覆层厚度约1 mm;显微硬度650 HV,熔覆层组织致密、晶粒细小,与12CrNi3A钢呈冶金结合;熔覆层的耐磨性优于凸轮本体,凸轮轴修复质量好,满足使用要求。采用激光熔覆技术实现了喷油泵凸轮轴严重损伤升程表面的修复,克服了常规修复手段易导致整轴畸变的问题。

Laser cladding remanufacturing technology of 12 CrNi3 A steel camshaft

A high hardness laser clad layer was obtained on the worn surface of 12 CrNi3 A steel camshaft cam for fuel injection pump by using a 2 k W fiber laser.The surface integrality,hardness,microstructure and properties of the clad layer were characterized by PT flaw detection,Vickers hardness tester,metallographic microscope and friction wear tester.The results show that the clad layer has a thickness of about1 mm and microhardness of about 650 HV,compact microstructure and fine grains,and metallurgical bonding with the 12 CrNi3 A steel.The wear resistance of the clad layer is better than that of the cam base material,and the repair quality of the camshaft is good to meet the use requirements.It is concluded that the laser cladding technology can be used to repair the severe damaged camshaft surface of the fuel injection pump,and to overcome the distortion problem of the whole axis easily caused by the conventional repair method.