(哈尔滨工业大学 金属精密热加工国防科技重点实验室, 哈尔滨 150001)
摘 要: 研究了TiCp/Ti复合材料中增强相TiC的形貌和缺陷。XRD和SEM分析表明,材料中的TiC以初生枝晶状和共晶短棒状为主,另外还存在细小块状TiC。材料的深腐蚀SEM观察发现,TiC枝晶表面存在生长条纹,内部存在孔洞。生长条纹是TiC枝晶在自由生长过程中由于周围温度和溶质浓度梯度的波动而产生的。TiC枝晶内部存在纯Ti析出物,该析出物在制样过程中被腐蚀而留下了孔洞。
关键字: 复合材料; 形貌; 缺陷
in-situ TiCp/Ti composite
(National Key Laboratory for Precision Hot Processing of Metal,
Harbin Institute of Technology, Harbin 150001, P.R.China)
Abstract:The morphologies and defects of TiC in TiCp/Ti composites were studied. The analysis results of XRD and SEM indicate that TiC mainly exists in the matrix with primary dendrite and short-bar shape eutectic. In addition, fine TiC particles are found. The growth stripe and the pore are observed at the surface and in the center of TiC in the deeply etched microstructure, respectively. It is considered that the growth strip is due to the fluctuation of temperature and solute concentration gradient during the free growth process of TiC dendrite. However, Ti precipitates are found in the center of TiC and deep etching of Ti precipitates leads to the appearance of the pore in SEM microstructure.
Key words: composite; morphology; defects