高性能结构钢高温热变形行为

THERMAL DEFORMATION BEHAVIOR OF HIGH-PERFORMANCE STRUCTURE STEEL AT HIGH TEMPERATURE

在变形量50%,变形速率0. 1 s^-1、1. 0 s^-1、10. 0 s^-1以及变形温度850~1 100℃的条件下,采用Gleeble3800热模拟实验机研究420 MPa高性能结构钢的高温热变形行为,对实验钢的应力-应变曲线进行了分析和表征。结果表明,在应变量小于0. 4时,变形应力明显增加,当应变量大于0. 4时,变形应力的变化趋于平缓;在一定的应变下,变形应力随着变形温度的增加而下降,随着变形速率的提高而上升;获得的变形应力数学模型较好的描述了实验钢的热变形行为。

Under the conditions of 50% deformation,deformation rates of 0. 1 s^-1,1. 0 s^-1,10. 0 s^-1 and deformation temperature of 850 ~ 1 100 ℃,the hot deformation behavior of 420 MPa high performance structural steel is study by Gleeble 3800 thermal simulator. The stress-strain curves of the tested steel are analyzed and characterized. The results show that when the strain is less than 0. 4,the deformation stress increases obviously,and the change of the deformation stress tends to be gentle when the strain is greater than 0. 4. Under a certain strain,the deformation stress decreases with the increase of deformation temperature,and increases with the increase of deformation rate. The obtained mathematical model of deformation stress describes the hot deformation behavior of the test steel well.