基于SPH结合FEM的喷丸残余应力数值模拟

针对以往有限元模型中弹丸数量较少且为规则阵列排布的缺陷,采用光滑粒子流体动力学法(Smoothed particle hydrodynamics,SPH)与有限元法(Finite element method,FEM)相结合的方法,对喷丸过程进行数值模拟;使用MATLAB对弹丸空间位置坐标进行随机化处理,形成了大量丸粒冲击工件表面的随机喷丸仿真模型。通过分析确定了喷丸饱和时间,研究了喷射角度、弹丸流量对残余应力场的影响。结果表明:在喷丸参数一定的条件下,存在相应的饱和喷丸时间;研究喷丸参数对残余应力的影响时,应在喷丸达到饱和时间之后提取残余应力值;喷射角度增大,残余压应力增大;开始时弹丸流量增大,残余压应力会有所增大,但当其达到饱和值后,残余压应力不再变化。

Numerical Simulations for Residual Stress Field of Shot-peening Based on SPH Coupled with FEM

In previous numerical models, the number of shots is inadequate and its distributions is in a regular array. To overcome there defects, the smoothed particle hydrodynamics (SPH) and finite element method (FEM) were coupled to simulate the shotpeening process. By MATLAB programming to deal with the shots space coordinates, a random shotpeening model with many shots impacting the component surface was built. The shotpeening saturation time, the influence of impact angle and mass flow on the residual stress field were analyzed. The results show that in the given condition, the corresponding saturated shot peening time exists. The residual stress value should be extracted after reaching the shot peening saturated time in the effect of shot peening parameters on the residual stress research. With the increase of the impact angle and mass flow, the residual pressure stress is improved. However, the residual stress field remains unchanged when the mass flow reaches a certain extent.