Abstract: The cutting forces and the abrasive velocity in the contact area of the workpiece were changed when the SCA pneumatic grinding wheel was used to process the irregular curved surface. In order to solve the problems of uneven material removal at different curvatures of the workpieces, the modified Rowe dilatancy theory was proposed to establish the grinding wheel cutting force model, and the modified material removal model of the pneumatic grinding wheel under the non-uniform curvature surfaces was proposed herein. The model of SCA pueumatic grinding wheel was established by EDEM software. The influences of workpiece curvatures on contact forces and abrasive velocity in contact areas were analyzed when the amount of compression of grinding wheel was as 1.5 mm. The modified material removal model was verified by finishing experiments. The results show that the modified material removal model MAE(mean absolute error) is as 0.095, while the original material removal model MAE is as 0.291, The revised material removal model may be used for quantitative analysis in the SCA wheel polishing processes, scratches on the machined surfaces of the workpiece are significantly reduced.

Key words: soft consolidation abrasives（SCA）, non-uniform curvature, dilatancy effect, material removal model

摘要： 针对软固结磨粒气压砂轮在加工异形曲面时，工件所受的切削力以及接触区内磨粒速度因工件曲率发生变化，导致工件不同曲率处材料去除量不均匀的问题， 基于修正的Rowe剪胀理论建立砂轮切削力模型，提出了非一致曲率表面下修正的气压砂轮材料去除模型。通过EDEM软件建立了软固结磨粒气压砂轮模型，分析了砂轮下压量为1.5 mm时工件曲率对接触力以及接触区内磨粒速度的影响。搭建气压砂轮加工试验平台，通过光整加工试验验证修正的材料去除模型。研究结果表明：修正的材料去除模型平均绝对值误差为0.095，而原始的材料去除模型平均绝对值误差为0.291，说明修正的材料去除模型可以用于气压砂轮抛光过程中的定量分析，且工件加工表面划痕明显减少。

关键词: 软固结磨粒群, 非一致曲率, 剪胀效应, 材料去除模型