冶金工程学院

Journal of Materials Engineering and Performance (SCI)

中文关键字：本构方程，流动应力，修正JC模型；Ti-6Al-4V合金，英文关键字：constitutive equation; flow stress; modified Johns

A modified Johnson-Cook constitutive equation of Ti-6Al-4V alloy is proposed based on hot compression tests performed in the temperature range of 1073-1323 K and strain rate 0.001-1 s21. The experimental stress-strain data were employed to develop the modified Johnson-Cook constitutive equation of different phase regimes (a + b and b phase). The predicted flow stresses using the developed equation were compared with experimental data. Correlation coefficient (R) and average absolute relative error (AARE) were introduced to verify the validity of the constitutive equation. The values of R and AARE for a + b phase were 0.990 and 7.81%, respectively. And in b phase region, the values of R and AARE were 0.985 and 10.36%, respectively. Meanwhile, the accuracy, the number of material constants involved, and the computational time required of the constitutive equation were evaluated by comparing with a strain-compensated Arrhenius-type constitutive equation. The results indicate that accuracy of modified Johnson- Cook constitutive equation is higher than that of compensated Arrhenius-type model at a + b phase, while lower at single b phase region. Meanwhile, the time required for evaluating the material constants of modified Johnson-Cook constitutive equation is much shorter than that of the strain-compensated Arrhenius type ones.

蔡军

翟鹏,李付国

yangjie,Kuaishe Wang,caijun

Journal paper

卷：24

期：1

页：32-44

no

2015-01-01