泡沫金属压痕试验的数值模拟及其反演

NUMERICAL SIMULATION FOR CONE INDENTATION OF METALLIC FOAMS AND THE REVERSE ANALYSIS

在理论研究的基础上,将泡沫金属压痕试验的有限元数值模拟结果与用无量纲分析法构造出的一系列无量纲函数相结合,建立了泡沫金属压痕试验中载荷-压痕深度关系曲线与泡沫金属的弹塑性材料参数之间的联系．利用这种联系,就可以实现用压痕试验通过反演分析来确定泡沫金属的材料参数．研究结果表明,泡沫金属材料的杨氏模量,屈服强度及塑性可压缩因子等参数均可由其压痕试验唯一的确定,但其塑性平台区终点应变的确定还需进一步的研究．

Indentation testing is a popular method used to determine the mechanical properties of materials. In this paper, finite element simulations are carried out for cone indentation of metallic foams with 80 different material parameters. The numerical results combined with the dimensionless analysis method are used to establish the relationship between the cone indentation behavior and the elastoplastic material parameters of metallic foams. Based upon the relationship, a reverse analysis is developed so that the elastoplastic properties of metallic foams can be extracted from the cone indentation data. Obtained results show that the Young＇s modulus, yield strength, and plastic compression coefficient of metallic foams can be unambiguously determined by the developed reverse method. However, some supplement information is needed in order to evaluate the densification strain.