低速大熔滴模拟热喷涂熔滴扁平化过程的研究

Investigation of splatting process of thermal sprayed with low speed big droplets

运用雷诺力学相似准则，采用Ｓｎ－Ｐｂ合金低速大熔滴，模拟研究了热喷涂熔滴碰撞基体后的扁平化过程．研究表明：粒子的结合性能与粒子的尺寸、结合面积、粘结力、粒子内部及界面的热应力有关．适当提高粒子碰撞速度、有效地粗化基体表面和采用预热或减缓粒子在塑性温度点以上的停留时间，可有效地提高粒子的结合面积、粘结力和释放粒子的热应力，从而提高粒子的结合强度．

The rule of reynolds mechanical simulation is used in investigating the process of splatting after the thermal sprayed low speed big droplets impinged on the substrate with Sn Pb alloy droplets. It shows that the particle's bonding property is related to the particle's dimension, the bonding area, the bonding force and the thermal stresses in the particle and between particle and substrate. The bond strength between particle and substrate can be improved by increasing the particle's impinging speed, coarsening the substrate's surface and preheating the surface, etc.