摘要
为研究喷丸强化对工件残余应力的影响及由表面粗糙度变化引起的应力集中,以Abaqus软件为平台,7075铝合金为研究对象,建立喷丸强化有限元预测模型,并与公开发表文献中数据对比,验证模型的准确性。在此基础上以弹丸喷射速度、丸粒材质、弹丸数量等为因素,设计单因素试验、正交试验模拟分析了喷丸对应力集中及残余应力的影响,以轮廓最大高度R_(z),轮廓单元平均宽度R_(sm)表征表面粗糙度。结果表明:弹丸喷射速度与残余应力呈线性关系;当弹丸材质不同,质量相近时,造成的冲击力相近,因此对残余应力的影响几乎一致,故在相同条件下,材质的密度越大,残余应力值越大;弹丸数量增加,最大残余压应力值随之变大;通过极差分析确定了喷丸参数对R_(z)、R_(sm)及应力集中因子K_(t)的影响程度,以表面粗糙度及应力集中因子的最小值为目标参数,选取了最优工艺参数组合。
To study the effect of shot peening on residual stress of workpiece and stress concentration caused by surface roughness change.Based on Abaqus software and 7075 aluminum alloy as the research object,the finite element prediction model of shot peening strengthening was established,and the accuracy of the model was verified by comparing with the data in published literature.On this basis,the effects of shot peening on stress concentration and residual stress were simulated by single factor test and orthogonal test,and the maximum height of contour R_(z)and the average width of contour element R_(sm)were used to characterize the surface roughness.The results show that there is a linear relationship between projectile ejection velocity and residual stress.When the projectile material is different and the mass is similar,the impact force is similar,so the impact on the residual stress is almost the same,so under the same conditions,the greater the density of the material,the greater the residual stress value;The maximum residual compressive stress increases with the increase of the number of projectiles.The effects of shot peening parameters on R_(z),R_(sm)and stress concentration factor K_(t)were determined by range analysis.The optimal process parameters were selected by taking the minimum value of surface roughness and stress concentration factor as the target parameters.
作者
付宏鸽
孙青杰
王伟帅
白帆
FU Hong-ge;SUN Qing-jie;WANG Wei-shuai;BAI Fan(School of Mechanical Engineering,North China Institute of Aerospace Engineering,Langfang 065000;College of Mechanical Engineering,Tianjin University of Science and Technology,Tianjin 300222)
出处
《机械设计》
CSCD
北大核心
2022年第S02期51-55,共5页
Journal of Machine Design
基金
北华航天工业学院博士科研启动基金项目(BKY202109)
北华航天工业学院硕士研究生创新资助项目(YKY-2021-01)
河北省教育厅在读研究生创新能力培养资助项目(CXZZSS2021158)
关键词
应力集中
残余应力
有限元分析
轮廓最大高度
轮廓单元平均宽度
stress concentration
residual stress
finite element analysis
maximum contour height
average width of contour cell
