低温超音速喷涂团聚铁粒子沉积的SPH模拟

SPH simulation on agglomerate Fe particle deposition in low temperature high velocity air fuel spraying process

为了研究纳米团聚粒子形态对涂层特性的影响,应用SPH方法研究了低温超音速火焰喷涂金属团聚粒子的沉积行为.结果表明,纳米粒子团聚为微米级粒子后,基体碰撞出现了飞溅现象,应变变化明显.团聚粒子的等效塑性应变小于普通微米粒子,但团聚粒子的面积扩大比大于普通微米粒子.沉积过程中,当超过临界沉积速度后,金属团聚粒子与基体之间存在过渡区域,过渡区域随粒子速度的增加而扩大.

In order to study the effect of the agglomerate metal particle on the coatings building-up,the agglomerate nano metal particle deposition characteristics with smoothed particle hydrodynamics(SPH) were simulated in low temperature high velocity air fuel(LTHVAF) thermal spraying process.The results show that the agglomerate particles are splashed when the agglomerate particles impact on the substrate.During the deposition process,the effective strain of agglomerate particle is larger than that of the micron particle,but the area ratio of the agglomerate particle is less.At the same time,the pervasion occurs when the metal particle impacts on the substrate,which increases with the particle velocity.