PCVD法制备的Ti-Si-C-N纳米复合超硬薄膜的高温氧化行为  

OXIDATION BEHAVIOR OF Ti-Si-C-N SUPERHARD NANOCOMPOSITE COATINGS DEPOSITED BY PCVD

作　　者：郭岩[1] 徐彬[1] 吴贵智[1] 马胜利[1] 徐可为[1] 

机构地区：[1]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《金属学报》2007年第2期159-164,共6页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目50371067和50671079;国家自然科学基金委重大国际合作项目50420130033;国家重点基础研究发展规划项目2004CB619302;教育部新世纪优秀人才支持计划项目NCET-04-0934;西安交通大学博士学位论文基金项目X020-082062资助~~

摘　　要：用脉冲直流等离子体辅助化学气相沉积(PCVD)方法在高速钢基体上沉积出Ti-Si-C-N超硬薄膜．XRD,XPS及HRTEM等测试表明,薄膜由纳米晶/非晶复合结构组成(nc-Ti(C,N)/a-Si_3N_4/a-C-C或nc-Ti(C,N)/h-Si_3N_4/a- Si_3N4/a-C-C)．Ti(C,N)显示(200)晶面择优取向．高温氧化实验显示：随Ti含量降低和Si含量增大,Ti-Si-C-N薄膜的抗氧化温度逐步提高；当Ti含量为8．7%、Si含量为17．8%时,薄膜中出现少量晶化的密排六方结构的h-Si_3N_4,弥散分布在非晶基体中,薄膜抗氧化温度达到900℃．Ti-Si-C-N薄膜的氧化过程分为增重和失重两个阶段,进入失重阶段后薄膜很快失效．Superhard nanocomposite Ti-Si-C-N coatings were deposited on substrate of high speed steel using an industrial pulsed d.c. plasma chemical vapor deposition （PCVD） set-up. Detailed microstructure examined by means of XRD, XPS and TEM suggested that the Ti-Si-C-N coatings were the nanocomposite structure composed of nanocrystalline Ti（C, N） and amorphous carbon and Si3N4, occasionally h-Si3N4. Ti（C, N） showed a strong （200） preferred orientation. With increasing of Ti content and decreasing of Si content, high-temperature oxidation resistance was improved gradually. When Ti and Si contents were 8.7% and 17.8%, respectively, the coating exhibited the better high temperature （900 ℃） oxidation resistance, which is related to the increase of amorphous Si3N4 and h-Si3N4 appeared dispersively in the amorphous matrix, both can act as an efficient barrier against oxygen diffusion. Two-stage oxidation process involving mass gain and loss were observed, the failure of the coating took place in the process of mass loss.

关 键 词：Ti-Si-C-N 纳米复合超硬薄膜 晶粒尺寸 抗氧化温度 

分 类 号：TG174.44[金属学及工艺—金属表面处理]