航空用不锈钢磨粒流光整加工表面完整性研究

Study on Surface Integrity of Aviation Stainless Steel in Abrasive Flow Machining

为研究磨粒流光整加工不锈钢闭式整体叶环的表面完整性,通过对电火花制备的不锈钢试样进行加工时间、加工压强及磨料目数的单因素试验,研究3个因素对加工后表面完整性的影响。结果表明:表面粗糙度Ra随着加工时间的增加而降低,从初始时的1.459μm降至60 min时的0.193μm,降低速率越来越慢,最后趋于稳定。磨粒流加工有效去除了加工表面再铸层。显微硬度在加工后明显降低,由450~950 HV降至270~350 HV且分布均匀性得到改善。显微硬度随着加工时间的增加整体上呈降低趋势,并出现了一定的加工硬化现象。在使用不同目数的磨料进行磨粒流加工后,残余应力由拉应力变为压应力。随着加工时间和加工压强的增加,试样表面越平整,抛光效果越好。

To study the surface integrity of the stainless steel closed integral bling in abrasive flow machining,single factor tests of processing time,processing pressure and abrasive mesh size are carried out on the stainless steel samples prepared by electrical discharge machining,and the influence of three factors on the surface integrity after machining is investigated.The surface roughness value Ra decreases with the increase of processing time,from 1.459μm at the initial time to 0.193μm at 60 min.The surface roughness decreases at a slower and slower rate,and finally tends to stabilize.The recast layer is effectively removed by abrasive flow machining,and the microhardness decreases from 450~950 HV to 270~350 HV after machining,and the distribution uniformity is improved.The microhardness decreases with the increase of processing time,and some work hardening occurs.The residual stress changes from tensile stress to compressive stress after abrasive flow machining with different mesh numbers of abrasives.With the increase of processing time and pressure,the smoother the sample surface is,the better the polishing effect will be.