摘要
采用Gleeble-3500热模拟试验机对GH984G合金在应变速率为1s^(-1)、温度在1000~1175℃范围内进行了热拉伸试验,并对拉伸后试样断口及轴向显微组织进行了分析,以评估GH984G合金的热拉伸行为。结果表明:GH984G合金在1000~1175℃拉伸时具有良好的塑性,断面收缩率均≥85.4%,在1100℃时塑性最好,断面收缩率为96.2%;合金在不同温度下的拉伸断口均发生了明显的截面颈缩现象,断口缩减量、单位面积内韧窝及孔洞数量均随着温度的升高而逐渐增加,温度升到1100℃时,断口缩减量、单位面积内韧窝及孔洞数量最大,塑性最佳。温度进一步升高,断口缩减量、韧窝及孔洞数量开始缓慢减小,温度超过1150℃时,明显减小,塑性下降;合金的动态再结晶面积分数随温度的升高而逐渐增加,温度在1050~1200℃时发生了完全动态再结晶。拉伸应变速率为1s-1时,GH984G合金最佳的热变形温度范围为1050~1175℃。
The hot tensile test of GH984G alloy was carried out at the strain rate of 1 s^(-1) and temperature range of 1000-1175℃ by Gleeble-3500 thermal simulation tester,and the fractured surface and axial microstructure of the tensile specimens were analyzed to evaluate the hot tensile behavior of GH984G alloy.The results show that GH984G alloy has good plasticity at 1000-1175℃,and the percentage reduction of the section is more than 85.4%,and has best plasticity at 1100℃ and the percentage reduction of the section is 96.2%;The obvious section necking occurs in the tensile fracture of the alloy at different temperatures,the reduction of fracture surface,the number of pores and dimples per unit area increase with the increase of temperature.When the temperature rises to 1100℃,the reduction of fracture surface and the number of pores and dimples per unit area are the largest and the plasticity is the best.With the further increase of temperature,the reduction of fracture surface and the number of pores and dimples begin to decrease slowly.When the temperature exceeds 1150℃,it decreases obviously and the plasticity decreases,too;The area fraction of dynamic recrystallization increases with the increase of temperature,and complete dynamic recrystallization occurs at 1050-1200℃.When the tensile strain rate is 1 s^(-1),the optimum hot deformation temperature range of GH984G alloy is 1050-1175℃.
作者
高佩
GAO Pei(Jiangsu Yinhuan Precision Steel Tube Co.,Ltd.,Yixing 214203,China;Materials Science and Engineering School,Jiangsu University,Zhenjiang 212013,China)
出处
《压力容器》
北大核心
2021年第9期11-17,共7页
Pressure Vessel Technology
基金
江苏省高等学校自然科学研究面上项目(19KJB430001)
江苏省高端结构材料重点实验室开放基金资助项目(hsm1808)。
