基于微切削模型的不锈钢研磨表面残余应力规律

Law of Residual Stress on Stainless Steel Lapping Surface Based on Micro Cutting Mode

目的基于单颗粒微切削模型,研究分析研磨工艺对HR-2抗氢不锈钢工件表面残余应力的演化规律与产生机制的影响。方法建立研磨磨粒单颗粒微切削残余应力数学模型,采用正交试验获得研磨工艺参数与表面残余应力大小、磨粒微切削切深和切向力回归方程,利用单因素试验对研磨工艺进行验证,获得研磨工艺参数对表面残余应力大小、表面磨粒切深和切向力的影响规律,并开展单因素试验结果与数学模型计算结果对比研究。结果试验中,磨粒粒径从10μm变化为50μm时,残余应力从–130 MPa变化至–345MPa;研磨压力从10 N变化至50 N时,残余应力从–135 MPa变化至–253 MPa;而转速的变化对残余应力结果的影响规律不显著。不同工艺参数试验中,模型所得计算值和试验值误差基本在10%以内。结论根据正交试验结果和单因素试验得出,研磨工艺对残余应力影响的显著度从高到低为磨粒粒径>研磨压力>研磨转速,磨粒切深和切向力与残余应力关系显著,建立的单颗粒研磨模型可以预测不同研磨工艺参数条件下的残余应力产生规律。

The work aims to analyze the evolution rule and mechanism of lapping process on the surface residual stress of HR-2 hydrogen steel based on the micro cutting model.A mathematical model of single-grain micro-cutting residual stress of abrasive particles was established.Orthogonal experiments were conducted to obtain the regression equations of lapping process parameters and surface residual stress,micro-cutting depth of abrasive particles and tangential force.Single-factor experiments were conducted to verify the lapping process.The influence of the lapping process parameters on the surface residual stress,the cut depth of the abrasive particles and the tangential force was obtained.And a comparative study between the experimental results and the mathematical model calculation results was carried out.The residual stress changed from–130 MPa to–345 MPa when the abrasive particle size was changed from 10μm to 50μm,and the residual stress changed from–135 MPa to–253 MPa when the lapping pressure was changed from 10 N to 50 N.The change of the rotation speed had no significant effect on the residual stress result.In the test of different process parameters,the error between the calculated value and the experimental value of the model was basically within 10%.Based on test results,it is concluded that the significant degree of influence of the lapping process on the residual stress from high to low is:abrasive particle size,lapping pressure,lapping speed;abrasive particle depth and tangential force have significant relationships with residual stress.The single particle lapping model can predict the law of residual stress under different lapping process parameters.