激光雕刻非光滑表面的微观组织和性能研究

Study on microstructure and properties of nonsmooth surface made by laser carving

采用激光雕刻技术在高速钢表面形成非光滑鳞片形态,利用扫描电镜、金相显微镜、X射线衍射仪分析了在激光雕刻快热、快冷的条件下的微观组织及其形成原因。结果表明,熔化区有极细胞状组织、极细枝状晶的形成;相变区晶粒得到细化,碳化物尺寸减小;热影响区碳化物聚集长大。利用显微硬度计、ML-100磨料磨损试验机考察非光滑表面的硬度及耐磨性。结果表明,硬度最高可达1120HV,抗磨粒磨损性能是未处理前的3.3倍。非光滑表面耐磨性提高的原因是细晶强化、弥散强化、固溶强化和仿生效应。

Bionic squama with nonsmooth surface was made by laser carving on the surface of high speed steel.Squama microstructure and its formation mechanism under rapid melting and rapid solidification conditions like laser carving were investigated by means of scanning electron microscopy,optical microscopy and X-ray diffraction.The results indicate that in the melted zone there are very fine cell structure and dendrite.In the phase transformation zone the size of carbides decreases and in the heat affected zone carbides congregate and grow up.Microhardness was measured by means of a microhardness tester and abrasive wear resistance was tested by ML-100 wear testing machine.It is shown that the highest hardness of high-speed steel reachs 1120HV after laser carving and abrasive wear resistance of bionic nonsmooth surface is three times higher than that of smooth surface.The reason for abrasive wear resistance enhancement of bionic nonsmooth surface is grain super-refining strengthening,dispersion strengthening,solution strengthening and effect of bionics.