盲孔法测量QT700材料应变释放系数的研究  

Study on Measuring Strain Release Coefficient of QT700 Material by Blind Hole Method

作　　者：汪友路 钱冬冬 解明国[2] 张学斌[1] WANG Youlu;QIAN Dongdong;XIE Mingguo;ZHANG Xuebin(School of Materials Science and Engineering,Hefei University of Technology,Hefei 230009,China;Hefei Casting and Forging Factory,Anhui Heli Co.,Ltd.,Hefei 230601,China)

机构地区：[1]合肥工业大学材料科学与工程学院,安徽合肥230009 [2]安徽合力股份有限公司合肥铸锻厂,安徽合肥230601

出　　处：《铸造技术》2022年第6期462-467,共6页Foundry Technology

摘　　要：应变释放系数A、B值是盲孔法测量残余应力的重要参数,目前国内外对灰铸铁及钢的应变释放系数的研究较多,对球墨铸铁应变释放系数的研究相对缺乏。论文采用盲孔法对QT700的应变释放系数值进行了标定,并对标定过程中最重要的钻孔步骤进行了改进,采用高速钻机(转速90000 rpm)及圆柱形铣刀进行钻孔,减小了常规方法的切削应力,提高了测试精度。在此基础上对应变释放系数A、B值进行了塑性修正,将最大相对误差由97.08%减小到3.18%。实验得到的QT700材料的应变释放系数及塑性修正公式均可直接用于实际QT700材料残余应力测量。The blind hole method was used to calibrate the strain release coefficient of QT700,and the most important drilling step in the calibration process was improved.A high-speed drill(rotational speed of 90000 rpm)and cylindrical milling cutter were used to drill the hole.The results show that the cutting stress of conventional method is reduced and the testing accuracy is improved.On this basis,the values of strain release coefficients A and B are plastic modified,and the maximum relative error is reduced from 97.08% to 3.18%.The strain release coefficient and plasticity correction formula of QT700 material can be directly used to measure the residual stress of QT700 material.

关 键 词：应变释放系数 盲孔法 残余应力 QT700 塑性修正 

分 类 号：TG164.2[金属学及工艺—热处理]