Transient thermo-mechanical coupled in diamond film and the crack of film during preparation
According to the special case of high temperature variation rate and strain rate for diamond film produced by DC plasma jet method,a transient thermo-mechanical coupled model for the cooling process of diamond film and Mo substrate was developed.The direct coupled finite element method was used to simulate the transient thermal stresses in diamond film during the cooling period after the film deposition.The residual thermal stresses of diamond film were calculated and compared respectively under two conditions of real uneven temperature fields and unreal even temperature fields.Based on the simulated results of stresses,the moment and cause of diamond film cracking were analyzed.The conclusions are as the follows:(1) the thermal stresses in diamond film increase with the increase of cooling time,but the maximum first principal tensile stress may reach the fracture strength of common diamond film before the film cools to room temperature;(2) the excessive tensile stress at the film edge causes the film cracking;(3) in order to reduce the thermal (residual ) stresses and increase the finished product ratio of diamond film,it is essential to further improve the temperature uniformity.
Diamond film Thermo-mechanical coupled Transient crack Residual thermal stresses
Dapei Tang Qing Gao Yinghui Li Fanxiu Lü
School of Mechanics and Engineering,Southwest Jiaotong University,610031,Chengdu,China School of Materials Science,University of Science and Technology Beijing,100083,Beijing,China
国际会议
成都
英文
391-395
2009-10-16（万方平台首次上网日期，不代表论文的发表时间）