Fatigue crack growth along interface between metal and ceramics submicron-thick films in inert environment
Fatigue crack growth along interface between metal and ceramics submicron-thick films in inert environment
复制标题
DOI：
10.1016/j.actamat.2005.08.026
复制
发表时间：
2006
期刊：
影响因子：
9.4
通讯作者：
H. Hirakata;M. Kitazawa;T. Kitamura
中科院分区：
文献类型：
--
作者：
H. Hirakata;M. Kitazawa;T. Kitamura
在惰性环境中，对亚微米薄膜(Cu/SiN)界面的疲劳裂纹扩展进行了实验研究。为便于控制裂纹扩展，提出了一种只有一个界面裂纹的改进的四点弯曲试件。结果表明，即使在低湿度的惰性环境中(相对湿度3.5±1%)，在循环载荷作用下，铜/氮化硅界面仍有明显的裂纹扩展。裂纹扩展速率da/dN由应力强度因子范围ΔKi控制，在da/dN−Δ曲线上观察到以下三个阶段：门槛、稳定扩展和临界扩展。由于薄膜的高屈服应力和衬底的约束，亚临界裂纹扩展区域很窄。空气中(相对湿度为50±10%)的生长也符合S型曲线，但湿度对生长有明显的促进作用。
The mechanical crack growth along the interface between submicron films (Cu/SiN) under fatigue is experimentally investigated in an inert environment. A modified four-point bend specimen which has only one interface crack to facilitate the control of crack growth is proposed for the tests. The results reveal that the clear interface crack between Cu and SiN grows under the cyclic load even in the low humidity of the inert environment (3.5±1% relative humidity (RH)). The crack growth rate, da/dN, is governed by the stress intensity factor range, ΔKi, and the following three stages are observed in the da/dN−ΔKicurve: threshold, stable growth and critical growth. The region of subcritical crack growth is quite narrow due to the high yield stress of the films and the constraint by the substrate. A similar sigmoidal relationship is obtained in the air (50±10% RH), though the growth is greatly accelerated by the humidity.