采用压痕实验确定线性强化弹塑性材料的弹性模量

DETERMINING THE ELASTIC MODULUS OF LINEARLY HARDENING ELASTOPLASTIC MATERIALS USING INDENTATION TESTS

利用有限元分析,该文尝试将双锥形压头压痕实验确定幂强化材料力学特性的方法应用于线性强化材料弹性模量的识别。研究发现,得到的弹性模量的误差与弹性模量和屈服极限的比值及线性强化参数m之间有密切的关系:弹性模量与屈服极限的比值小于45.4时,弹性模量的识别误差很小,可以认为识别结果不受材料线性强化特性的影响;弹性模量与屈服极限的比值大于45.4时,在线性强化参数m满足文中给定的条件时,可以认为识别结果不受材料线性强化特性的影响。

Recently,we have proposed an inverse approach to determine the elastic modulus of power-law engineering materials using indentation tests.In this study,we make an attempt to apply the method developed for power-law materials to the elastoplastic materials which exhibit a linearly hardening behaviour.It is found that the errors in the identified elastic modulus have a close relationship with the ratio of the elastic modulus to the yield strength and the linearly hardening parameter m.For the linearly hardening materials with ratios of the elastic modulus to the yield strength less than 45.4,the errors in the identified the elastic modulus are very small.For linearly hardening materials of which the ratios of the elastic modulus to the yield strength larger than 45.4,when the hardening parameter m satisfies the described conditions,the inverse approach developed for power-law materials may be applied to the materials exhibiting linearly hardening behaviours.