Elastic bending analysis of bilayered beams by an alternative two-variable method
Elastic bending analysis of bilayered beams by an alternative two-variable method
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DOI：
10.1016/j.euromechsol.2008.07.004
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发表时间：
2009-03
影响因子：
4.1
通讯作者：
Neng-Hui Zhang;Jian-zhong Chen
中科院分区：
文献类型：
--
作者：
Neng-Hui Zhang;Jian-zhong Chen
采用二变量法重新分析了双层梁在外弯矩和内应力作用下的热弹性弯曲问题。对零应力轴、零应变轴(即中性轴)、弯曲轴、质心轴以及零、单、双零应力轴的参数条件的差异进行了解析和数值研究。以典型的GaAs顶层/Si衬底为例，讨论了本模型与Stoney模型和Schueh模型的热弹性应力预测的比较。结果表明，一般情况下，中性轴与零应力轴并不重合，零应变轴或零应力轴的数目和位置不仅取决于薄膜与基材之间的弹性模量、厚度和/或热膨胀系数比，而且还取决于机械/热载荷比。
An alternative two-variable method is used to reanalyze thermoelastic bending problems of bilayered beams subjected to external moments and internal stresses. The differences among zero-stress axis, zero-strain axis (i.e. neutral axis), bending axis, centroidal axis, and the parameter conditions for null/single/dual zero-stress axes are investigated analytically and numerically. Comparisons of thermoelastic stress predictions by the present model with Stoney's model and Hsueh's model are discussed in a representative case of GaAs top coat/Si substrate wafers. Results showed that the neutral axis does not coincide with the zero-stress axis in the general case, and the numbers and the locations of zero-strain or zero-stress axes depend on not only elastic modulus, thickness and/or thermal expansion coefficient ratios between the film and the substrate but also mechanical/thermal loading ratio.