激光表面合金化层内枝状碳化钛的生长模式(英文)  

Microstructure and Growth Model of TiC Dendritic Crystals Produced by Laser Surface Alloying Technique

作　　者：田永生[1] 陈传忠[1] 王德云[1] 雷廷权[2] 

机构地区：[1]山东大学材料科学与工程学院,济南250061 [2]哈尔滨工业大学材料科学与工程学院,哈尔滨150001

出　　处：《应用激光》2005年第2期109-112,共4页Applied Laser

基　　金：山东省自然科学基金资助( No: 032090107)

摘　　要：纯钛表面预涂石墨粉后采用激光合金化处理。EPMA分析知合金化层内生成了TiC树枝状晶。理论分析表明,树枝状晶的生长方式为最初的结晶是通过连续生长方式形成枝状晶坯,其后枝状晶坯适于侧面生长的表面开始以螺旋方式长大。因此,枝状TiC的晶体形貌看似由多个细小的TiC颗粒线性排列构成。SAED选区衍射结果表明TiC是面心立方结构,点阵常数为α=0.43nm.Dendritic TiC was fabricated by laser surf ac e alloying of pure titanium with graphite powder. The microstructure of dendriti c TiC was investigated by means of SEM, EPMA and HRTEM and the growth model is t heoretically analyzed: They develop into dendritic crystals by the model of cont inuous growth at the beginning of solidification and then each of the dendritic arms acts as nuclei on which the lateral growth begin. So, the crystal surfaces that are suited to lateral growth develop fully by the model of spiral growth an d the final morphology of dendritic TiC looks like composed of tiny grains of Ti C in a linear arrangement. SAED results show that the lattice structure of TiC i s face centered cubic (fcc) and its lattice parameter is α=0.43nm.

关 键 词：激光表面合金化 生长模式 碳化钛 面心立方结构 树枝状晶 生长方式 合金化处理 TIC颗粒 EPMA 晶体形貌 选区衍射 SAED 点阵常数 石墨粉 钛表面 分析表 螺旋 

分 类 号：TQ174.758[化学工程—陶瓷工业] TG174.445[化学工程—硅酸盐工业]