抄録
Tension-compression asymmetry of plastic deformation of magnesium alloys has been known to affect plastic formability in several metal forming processes. However, in most of works on the tension-compression asymmetry, the result of uniaxial tension was compared with that of uniaxial compression. In the present study, the plastic deformation behavior of AZ31 magnesium alloys in uniaxial tension was investigated and compared with those in equi-biaxial compression, in which the macroscopic deformation was equivalent to that of uniaxial tension. It was found that the equi-plastic work point obtained by equi-biaxial compression was on the same isotropic yield curve with that by uniaxial tension, in the early stage of plastic deformation. The crystal orientation measurement results also revealed that the twin area fractions as well as active twin systems by uniaxial tension were almost the same with those by equi-biaxial compression. These results imply that the difference between deformation patterns by uniaxial tension and by uniaxial compression is primary cause of the tension-compression asymmetry of magnesium alloys.
