CAJ | 학술논문

在应变速率为1×10-3~1 s-1、温度为300~450℃条件下,采用Gleeble-3500型热模拟机对Mg-1.3Zn-1.7Ca (质量分数,%)镁合金(ZX115)进行单轴热压缩实验;通过分析ZX115镁合金的真应力-真应变曲线,探讨变形温度和应变速率对其流变曲线中峰值应力、峰值应变及Zener-Hollomom参数的影响,建立描述该合金高温压缩变形的本构方程.将本构方程应用于有限元分析软件 DEFORM 3D中,并对ZX115镁合金热压缩过程进行数值模拟,利用后处理程序,分析工件内部的应变速率场、应变场和温度场变化.研究表明:温度越高或应变速率越低时,流变曲线所达到的峰值应力越小,而在相同的应变速率下,峰值应变也随着变形温度的升高而明显减小;ZX115合金热压缩过程具有明显的变形不均匀性,为了合理控制变形后的再结晶晶粒尺寸,可适当降低形变温度和应变速率.
재응변속솔위1×10-3~1 s-1、온도위300~450℃조건하,채용Gleeble-3500형열모의궤대Mg-1.3Zn-1.7Ca (질량분수,%)미합금(ZX115)진행단축열압축실험;통과분석ZX115미합금적진응력-진응변곡선,탐토변형온도화응변속솔대기류변곡선중봉치응력、봉치응변급Zener-Hollomom삼수적영향,건립묘술해합금고온압축변형적본구방정.장본구방정응용우유한원분석연건 DEFORM 3D중,병대ZX115미합금열압축과정진행수치모의,이용후처리정서,분석공건내부적응변속솔장、응변장화온도장변화.연구표명:온도월고혹응변속솔월저시,류변곡선소체도적봉치응력월소,이재상동적응변속솔하,봉치응변야수착변형온도적승고이명현감소;ZX115합금열압축과정구유명현적변형불균균성,위료합리공제변형후적재결정정립척촌,가괄당강저형변온도화응변속솔.
The hot compressions of Mg-1.3Zn-1.7Ca (mass fraction, %)magnesium alloy (ZX115) were carried out on Gleeble-3500 thermal simulator at a strain rate of 1×10-3-1 s-1 and temperature range of 300-450℃. Based on the true stress-strain curves of ZX115 magnesium alloy obtained from experiments, the effects of deformation temperatures and strain rates on the peak stress, peak strain and Zener-Hollomon parameter were discussed, and the constitutive equations were established to describe the hot compression of ZX115 magnesium alloy. These constitutive equations were applied into finite element analysis software DEFORM 3D and then the hot compressions of ZX115 magnesium alloy were simulated. The variation and distribution of strain rate, strain and temperature in the compressed workpiece were analyzed by the post-processing procedures. The results show that peak stress decreases with increasing the deformation temperature or decreasing the strain rate, and the peak strain decreases with increasing the temperature under a given strain rate. The hot compressions of ZX115 magnesium alloy exhibits a nonuniform characteristic. In order to control the recrystallized grain size, the deformation temperature and strain rate should be necessarily decreased.