钇对激光熔覆钴基合金组织和高温腐蚀性能的影响

系统研究了在2Cr13和1Cr18Ni9Ti钢表面激光熔覆并含钇的钴基合金层的组织和表面涂盐的高温腐蚀行为,同时着重探讨了钇的作用。结果表明,添加钇的钴基合金覆层组织更细密,且与基体结合牢固;在表面涂有75％Na_2SO_4+25％NaCl盐膜条件下,其耐高温腐蚀性能获得极大提高;添加0.874％Y后,其表面能形成连续致密的保护性氧化膜,可阻碍氧、硫的扩散浸入,使其性能更佳。同时,添加钇后,内氧化层浅而细密,对内层合金元素向外表面扩散迁移起屏障作用。     

铸铁表面激光熔化添加Al—Y合金改性

在灰铸铁表面,采用高能激光束辐照,同时添加Al-Y合金粉末,在适当条件F,可得到含钇的改性层。利用金相、电子显微镜和电子探针观察并分析了改性层中钇的存在形态、深度迁移及在层断面上的分布。同时讨论了激光合金化系统的表面冶金过程及钇的某些热力学行为和迁移机制。     

激光熔覆TiC/Ti复合材料的组织及摩擦学性能

采用激光熔覆工艺,通过原位置换结晶反应在Ｔｉ６Ａｌ４Ｖ基材上制备出碳化物颗粒增强复合材料熔覆层,发现复合材料由均匀弥散分布的ＴｉＣ颗粒及β－Ｔｉ基体构成,且与基材呈冶金结合．干摩擦下其磨痕及磨屑扫描电镜分析表明,激光熔覆层具有较高的耐磨性的原因是复合材料中均匀弥散分布的ＴｉＣ粒子具有良好的抗磨作用     

Laser multi-layer cladding on ZM6 magnesium base alloy

A pulsed Nd: YAG laser is used in multi-layer cladding on ZM6 Mg base alloys. The microstructure is studied with an optical microscope and a scanning electron microscope (SEM). The composition within the layer was determined by electron probe microanalysis (EPMA). X-ray diffraction (XRD) was also used to investigate the phase of constitutes of the cladding zone. The results show that microstructure in solidified cladding layer changes much when treated by high energy laser beam. The microstructure of the ZM6 alloy consists of a-Mg and Mg9Nd, while the L-ZM6 of a-Mg, MggNd and a-Zr. The depth of the cladding is over 1 mm. Many fine particles were found to be distributed homogeneously throughout the matrix and the columnar grain grows along substrate.