冷喷涂中粒子形状和速度参数对撞击过程影响的数值模拟

发布时间：2018-06-30 17:45

本文选题：冷喷涂 + 碰撞特性　；参考：《中国科技论文》2015年22期

【摘要】：为了解冷喷涂中粒子形状和速度参数对其沉积过程的影响,采用显示有限元算法和任意拉格朗日-欧拉(ALE)网格划分法,研究了冷喷涂圆球和椭球状铝合金颗粒以不同初始速度撞击镁合金基板过程中,粒子和基板的变形行为和温度变化,以及对其反弹性能、基板坑深和最大相对接触面积的影响。结果表明:粒子形状对碰撞过程中粒子和基板的局部变形有较大影响,表现在对称截面的塑性变形和温度分布具有非对称性;椭球粒子沿其长轴方向垂直撞击基板时,截面局部变形比沿其短轴方向撞击基板情况剧烈;提高粒子撞击基板速度后,其反弹动能与其初始动能百分比不断降低,基板坑深增加,粒子和基板间的最大相对接触面积增加;但球形和椭圆形颗粒形状对基板坑深的影响较小。
[Abstract]:In order to understand the effect of particle shape and velocity parameters on the deposition process in cold spraying, a display finite element method and an arbitrary Lagrangian Euler (ale) mesh method were used. The deformation behavior and temperature change of particles and substrates during the impact of cold sprayed ball and ellipsoidal aluminum alloy particles on magnesium alloy substrate at different initial velocities were studied. The effects of the deformation behavior and temperature on the rebound performance, the depth of the substrate pit and the maximum relative contact area were also studied. The results show that the shape of particles has a great influence on the local deformation of particles and substrates during the collision, which is shown by the asymmetry of the plastic deformation and temperature distribution of the symmetrical section, and the ellipsoidal particles perpendicular to the substrate along its long axis. The local deformation of cross section is more severe than that of impacting the substrate along its short axis, the percentage of the rebound kinetic energy and its initial kinetic energy decreases continuously after increasing the particle impact velocity, and the pit depth of the substrate increases. The maximum relative contact area between the particles and the substrate increases, but the shape of the spherical and elliptical particles has little effect on the pit depth of the substrate.
【作者单位】：重庆大学低品位能源利用技术及系统教育部重点实验室;重庆大学动力工程学院;
【基金】：国家自然科学基金资助项目(50906104)
【分类号】：TG174.4

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