铸态P91耐热合金钢动态再结晶模型的建立  

Modeling of dynamic recrystallization for as-cast heat-resistant alloy steel P91

作　　者：李振晓 雷步芳[1,2] 付建华[1,2] 邓馗 

机构地区：[1]太原科技大学材料科学与工程学院,山西太原030024 [2]太原科技大学金属材料成形理论与技术山西省重点实验室,山西太原030024

出　　处：《锻压技术》2016年第1期121-127,共7页Forging & Stamping Technology

基　　金：国家自然科学基金重点项目(51135007);山西省回国留学人员科研资助项目(2015-086)

摘　　要：采用Gleeble-3500热模拟试验机在变形温度为900~1200℃,应变速率为0.01~5 s-1,总应变量为60%的变形条件下,进行了单向热压缩实验,获得铸态P91耐热合金钢的真实应力-应变曲线,对其进行分析发现热变形过程发生了动态再结晶,曲线共分为3种类型：加工硬化型、动态回复型和动态再结晶型。对热变形后的试样进行微观组织研究,分析变形温度和应变速率对动态再结晶组织演变的影响。以Avrami方程为基础,采用应力应变和平均晶粒尺寸等数据,通过线性回归的分析方法,分别建立了动态再结晶动力学模型、运动学模型和晶粒尺寸模型,得到了铸态P91耐热合金钢完整的动态再结晶模型。Using the Glecble -3500 thermal simulation test enginery, a single hot compression was carried out at the deformation tempera- ture ranging 900 - 1200 % , the strain rate ranging 0. 01 -5 s-1 and the deformation degree 60%. So the true stress-strain curves of as- cast heat-resistant alloy steel P91 were obtained. The analysis of the curves shows that the dynamic recrystallization occurs in the process of thermal deformation. The curves are divided into three types, including work hardening, dynamic recovery and recrystallization. Micro- structure analysis was carried out on the sample of thermal deformation. The influences of the deformation temperature and strain rate on the dynamic reerystallization micro-structure were analyzed. On the basis of Avrami equation, using the data of stress, strain and the average grain size, the dynamic recrystallization kinetics model, kinematics model and grain size model were established respectively through the analysis of linear regression, and then the complete dynamic recrystallization model of as-cast heat-resistant alloy steel P91 was obtained.

关 键 词：铸态P91耐热合金钢 真实应力-应变曲线 微观组织 动态再结晶模型 

分 类 号：TG142.33[一般工业技术—材料科学与工程]