摘要
通过直流磁控溅射方法制备出四个不同厚度的纳米Ti薄膜,并分别采用纳米压痕仪、电子薄膜应力分布测试仪研究了Ti薄膜的力学性能和残余应力大小,结合分形维数方法和原子力显微镜对薄膜表面粗糙度和表面形貌进行了分析。实验结果表明:随Ti薄膜厚度的增加,薄膜晶粒尺寸逐渐增大,表面粗糙度和残余应力值随厚度的增加先增大后减小,而Ti薄膜弹性模量和硬度随薄膜厚度增加呈现出先减小随后增大的趋势。当薄膜厚度为600,2400,3600nm时薄膜中存在残余压应力,厚度为1200nm时存在残余拉应力,薄膜中残余应力分布最为均匀,但此时薄膜具有较低的硬度和弹性模量值。分析得出Ti薄膜中存在残余拉应力会使薄膜硬度和弹性模量值变小,残余压应力反之。
Four nano-Ti films with different thickness were deposited by direct current magnetron sputtering （DCMS）. The mechanical properties and residual stress of the deposited Ti films were studied using nano indentation and electronic film stress distribution tester, surface roughness and surface morphology were analyzed using fractal dimension and the atomic force microscopy （AFM） respectively. The results show that, with the increase of the film thickness, the Ti crystal grain size increases gradually and both the surface roughness and residual stress increase first and then decrease, while the hardness and elastic modulus exhibit the opposite tendency. When the thickness of the deposited films is 600, 2400nm and 3600nm, the residual compressive stress exists; when the film thickness is 1200nm, the residual tensile stress exists, the distribution of residual stress is most uniform, when the residual tensile stress exists in the thin films, but the hardness and elastic modulus are lower. The analysis shows that residual tensile stress results in the decrease of the hardness and elastic modulus in Ti thin films, the residual compressive stress exhibits an opposite trend.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2015年第11期50-56,共7页
Journal of Materials Engineering
基金
北京市自然科学基金重大项目(3120001)
国家自然科学基金(51275105)
国家杰出青年科学基金(51125023)
关键词
薄膜
纳米压痕
分形维数
力学性能
film
nanoindentation
fractal dimension
mechanical property
