沉积温度对CVDTaC涂层择优取向及微观形貌影响-中国有色金属学报.PDF

18 8 2008 8 Vol.18 No.8 The Chinese Journal of Nonferrous Metals Aug. 2008 1004-0609(2008)08-1377-06 TaC ( 410083) TaCl -Ar-C H X TaC 5 3 6 800~1 200 TaC 220200αVAN DER DRIFT, MEAKINα=3 200α=1.5 220 TaC TB 332 A Surface morphology of TaC coating prepared by chemical vapor deposition and preferential growth mechanism of TaC grains CHEN Zhao-ke, XIONG Xiang, LI Guo-dong, XIAO Peng, ZHANG Hong-bo, WANG Ya-lei, HUANG Bai-yun (State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China) Abstract: TaC film was deposited by chemical vapor deposition technique at different temperatures with TaCl -Ar-C H 5 3 6 system. The surface morphology and preferential growth of TaC crystals were investigated by X-ray diffractometry and scanning electron microscopy. The results show that within 800−1 200 , TaC crystals of either ball-like particle with randomly preferential orientation, or dendrite with 220 orientation, or tetrahedral pyramid with 200 orientation are obtained with increasing of temperature. The preferential growth of TaC crystals can be fairly explained by the growth parameter α and VAN DER DRIFT model, MEAKIN model, selective evolution model at nanometric scale. The pyramidal shape crystals with 200 textures are formed at α = 3, while 220 formed at α = 1.5. Key words: TaC coatings; chemical vapor deposition; preferential growth; surface morphology C/C 370 [1−3] C/C[1−