论文部分内容阅读
采用激光熔注(LMI)技术在Q235钢表面制备WC颗粒增强的金属基复合材料(MMC)层。在激光熔注工艺特性和熔注层宏观特征分析的基础上,采用X射线衍射(XRD)和扫描电镜(SEM)对激光熔注层微观组织结构进行了分析。结果表明,WC颗粒注入到熔池的整个深度和宽度范围内,并且在熔注层中的分布比较均匀。WC颗粒的加入改变了熔池的化学成分,熔注层中出现了新相Fe3W3C。在熔注层上部存在较多Fe3W3C枝晶和少量枝晶间共晶,在熔注层下部枝晶数量减少,共晶数量明显增多。激光熔注层中不同WC颗粒周围反应层的尺寸和形貌存在很大差别。WC颗粒注入位置是决定反应层尺寸的重要因素。
A WC particle reinforced metal matrix composite (MMC) layer was prepared on the surface of Q235 steel by laser melting (LMI) technique. Based on the characteristics of laser melting process and macroscopic characteristics of melt layer, the microstructure of laser melt layer was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that WC particles are injected into the entire depth and width of the weld pool and are more uniformly distributed in the melt layer. The addition of WC particles changed the chemical composition of the molten pool, and the new phase Fe3W3C appeared in the molten layer. There are more Fe3W3C dendrites and a small amount of interdendritic eutectics in the upper part of the melt layer. The amount of dendrites in the lower part of the melt layer decreases, and the number of eutectic phases obviously increases. There are large differences in the size and morphology of the reactive layers around the different WC particles in the laser meltblown layer. The WC particle injection location is an important factor in determining the size of the reaction layer.