目的 提高淬硬12Cr2Ni4A钢的加工质量，消除工件表面残余应力。方法 采用普通磨削(OG)、超声振动辅助磨削(UVAG)以及超声振动辅助ELID磨削(UVAEG)3种磨削方式，分别对淬硬12Cr2Ni4A合金钢进行加工，分析3种加工方式下被加工工件的表面粗糙度以及残余应力。结果 在超声振动辅助磨削、超声振动辅助ELID磨削下，工件表面粗糙度都低于普通加工，而超声振动辅助ELID磨削后的工件表面质量最高，相对普通磨削加工，超声振动辅助ELID磨削后的表面粗糙度降低了66%，相对于超声振动辅助磨削，超声振动辅助ELID磨削后，表面粗糙度降低了约41%。对工件表面进行残余应力测定发现，普通磨削加工后工件表面为残余拉应力，而超声振动辅助磨削、超声振动辅助ELID磨削后的工件表面都产生了残余压应力，超声振动辅助ELID磨削后，工件表面的残余压应力高于超声振动辅助磨削约30%。普通磨削加工中，随磨削深度的增加，残余拉应力一直变大，而超声振动辅助磨削和超声振动辅助ELID磨削的残余压应力总体呈现减小的趋势。在磨削深度达到22.5 μm后，超声振动辅助磨削加工表面的残余压应力转变为残余拉应力。在超声振动辅助磨削和超声振动辅助ELID磨削后，随超声振幅的增大，表面残余压应力增大，超声振动辅助ELID磨削表面的残余压应力随占空比的增大而增大。结论 超声振动辅助ELID磨削加工后，能得到更小的表面粗糙度及更大的表面残余压应力。

This paper aims to improve the machining quality of hardened 12Cr2Ni4A steel, improve the machining accuracy and eliminate the residual stress on the workpiece surface. The hardened 12Cr2Ni4A alloy steel was processed by ordinary grinding (OG), ultrasonic vibration assisted grinding (UVAG) and ultrasonic vibration assisted ELID grinding (UVAEG) respectively. The surface roughness and residual stress of the workpiece machined under the three grinding modes were analyzed. The result was that the surface roughness of workpiece in UVAG and UVAEG was lower than that of OG, while the surface quality of workpiece after UVAEG was the highest. Compared with OG, the surface roughness decreased by 66% and 41% compared with UVAG; the residual stress measurement of workpiece surface showed that the surface of workpiece was residual tensile stress after OG, while residual compressive stress was produced after UVAG and UVAEG. The residual compressive stress of workpiece surface after UVAEG was about 30% higher than that of UVAG; in OG machining, the residual tensile stress had been increasing with the increase of the grinding depth, while the residual compressive stress of UVAG and UVAEG generally showed a decreasing trend. After the grinding depth reached 22.5 μm, the residual compressive stress on the machined surface of UVAG was transformed into residual tensile stress. The surface residual stress of UVAG and UVAEG increased with the increase of ultrasonic amplitude, and the surface residual stress of UVAEG increased with the increase of duty cycle. The conclusion is that UVAEG can obtain smaller surface roughness and larger surface residual compressive stress.