镶嵌粒子周围应变场的实验和数值模拟研究

Experimental and Numerically Simulative Investigation of Strain Field Induced by Micro Particle Impact

采用电子束云纹法对陶瓷粒子嵌入316L不锈钢表面后粒子周围应变场进行了实验测量,分析了镶嵌粒子周围应变场的分布规律;运用LS-DYNA对嵌入粒子周围及内部应变场进行了有限元模拟,并与实验结果进行比较;同时对2个粒子嵌入情况进行了有限元模拟,分析了粒子之间的距离对应变场及残余应力场的影响。结果表明:距嵌入粒子边缘距离越小,塑性应变越大,随着距离的增加,塑性应变逐渐减小,最后趋于零,x方向的最大塑性应变为10.75%,y方向的最大塑性应变为11.33%;实验结果和数值模拟结果吻合较好,最大误差为10.8%;粒子之间的距离越近,对应变场及残余应力场的分布范围影响越大,而对最大残余应力值的影响较小。

The microscopic deformation field induced by micro particle impact 316 Lstainless steel was determined using the electron moirémethod,the distribution of strain field around inlaid particles was analyzed.The strain field around embedded particles was simulated using LS-DYNA,and compared with the experimental results.The work was further extended to take into account the effect of two particles impinging and inlaying the substrate simultaneously.Special attention was paid on examining the effect of the separating distance between the particles upon the resultant residual stress field.The result show that there are the maximums value of plastic strain in the region where the particle contact with and with the increase of distance,it gradually decrease.The experimental results and numerical simulation results are in good agreement.The effective stress are significantly influenced by the particle velocity and embedded depth,the effect of separating distance between the impacting particles is relatively small.