软固结磨粒群内部磨粒拓扑结构对材料去除的影响

针对软固结磨粒气压砂轮光整加工新方法,研究气压砂轮软固结磨粒群的内部磨粒拓扑结构对被加工材料去除率的影响规律。建立气压砂轮材料去除机理模型,分析软固结磨粒群在单压缩载荷下内部细观组构参量及力链网络的演化过程,研究了软固结磨粒群的宏观力学特征与细观结构演化之间的关系,数值模拟了具有不同拓扑结构的磨粒层与工件接触区域内的应力分布规律。将软固结磨粒气压砂轮用于激光强化自由曲面光整加工实验,得到了磨粒目数及体积配比对材料去除量及表面粗糙度的影响规律,试验结果表明,软固结磨粒气压砂轮可用于激光强化表面的光整加工并获得良好的加工效果。

Influence of Topological Structure of Inter-particles in Softness Consolidation Abrasives on Material Removal

For a new finishing machining method-SCA(softness consolidation abrasives), the influence of internal abrasives’ topological structure of pneumatic grinding wheels with softness consolidation abrasives on materials removal rate is studied. The model of the materials removal mechanism of pneumatic grinding wheels is established. Meso-fabric parameters and the force chains net evolution of the abrasive group are analyzed under the monotonic loading. Relations between macro-mechanical properties and the meso-fabric evolution of the abrasive group is researched. The stress distributions on the area for abrasive layers with different topological structure contacting with workpieces are researched. The influence laws of abrasive’s mesh and volume matching on the material removal and surface roughness of workpieces can be concluded after a series of polishing experiments for the laser strengthening free-form surface by pneumatic wheels with softness consolidation abrasives. The experimental results show that the finishing machining by pneumatic grinding wheels with softness consolidation abrasives is available for the laser strengthening surface, which can achieve good processing effectiveness.