高ひずみ速度下における広いひずみ域に適用できる構成式の形式について(<小特集>衝撃小特集)

概要

論文の詳細を見る
It has been observed that a practical form of the constitutive equation, which is called a logarithmic or power law type, well represents an experimental stress-strain curve up to the strain rate of about 10^3 s^<-1>. The both type show gradual dependency of the strain rate on the stress. On the other hand, the deformation drug is governed by the viscous drug of dislocation at a high strain rate above 10^3 s^<-1>. In the range of high strain rate, the relation between strain rate and deformation drug is linear and of the Malvern types, where the over stress is a linear function of the atrain rate, satisfies the relation described adove. However, almost all of the constitutive equation have been investigated only in the small strain range up to now. In this paper, a new pracitical from of the constiutive equation which covers a wide strain rabge at high strain rates was investigated by comparing the experimental strain distribution with the numerical one for a lead specimen of finite length, which was impacted longitudinally. The results show that the new form, in which the logarithmic or the power law type is superimposed upon the Malvern type, is in good agreement with thw experiment results. it is also important that the strain rate appears as a function of the atrain in the form.
社団法人日本材料学会の論文
1990-12-15