摘要
目的针对平压头压入曲面材料的问题,提出了考虑曲面曲率时弹性模量的确定方法。方法首先利用有限元方法研究曲率对压入响应的影响,然后利用量纲分析与有限元方法,给出压入载荷的无量纲表达式,并提出考虑被压材料为曲面时弹性模量的确定方法,最后用数值算例验证方法的有效性。结果数值算例结果显示,本方法研究曲面材料的识别弹性模量的相对误差均小于4%,且精度较高。结论对于角膜、巩膜等生物软组织材料,用压入法确定材料力学特性时,材料表面曲率的影响不可忽略。
Objective For the problem of the indented solid with curved surface using fiat punch indentation, a method is proposed to identify the elastic modulus of materials. Methods Firstly, the effect of curvature on the indentation response is studied with the finite element method. Then, according to the dimensional analysis and finite element method, a dimensionless function expression of indention force can be obtained and the elastic modulus can be determined. Finally, the performance of the method is verified by the numerical experiments. Results The results of the numerical examples show that the maximum relative error of the identified elastic modulus of the indented solid with curved surface is 4% , which shows that the identified results are acceptable. Conclusions While the mechanical properties are determined by the indentation test, the effect of the curvature should not be ignored for certain soft tissues, such as cornea and sclera.
出处
《北京生物医学工程》
2012年第5期441-444,449,共5页
Beijing Biomedical Engineering
基金
北京市教育委员会科技计划面上项目(KM201110025009
KM201010025007)
北京市属市管高校人才强教计划资助项目(PHR201008398)
国家自然科学基金青年项目(11102123)资助
关键词
平压头
有限元方法
曲率
量纲分析
弹性模量
fiat indentor
finite element method
curvature
dimensional analysis
elastic modulus
