高速铣削高体积分数SiC_p/Al复合材料时PCD刀具磨损机理研究

Wear Mechanisms of PCD Tools in High-Speed Milling of High Volume Fraction of SiC_p/Al Composites

针对体积分数为65%的碳化硅颗粒增强铝基复合材料Si Cp/6063Al,采用聚晶金刚石(PCD)刀具对其进行了高速铣削试验,利用体视显微镜和扫描电镜(SEM)观察、分析PCD刀具前、后刀面磨损形貌的形成机理。研究结果表明:增强相Si C颗粒的高频刻划和冲击是导致刀具发生磨粒磨损、晶粒脱落、崩刃和剥落的主要原因;PCD刀具自身存在孔隙、组织不均等制造缺陷,加速了刀具发生晶粒脱落的情况发生,并在铝合金基体材料粘结物的产生、脱落过程中发生粘结磨损。

Based on the analysis of cutting characteristics of Si Cp/6063 Al aluminum matrix composite with 65% volume fraction of Si C particle-reinforced,the cutting experiments were conducted by using Polycrystalline Diamond（ PCD）tools,The stereo microscopy and SEM were used to observe and analyze tool wear on the rake face and flank face of tools.The results show that the high frequency impact and the scrap of Si C particles are the principle mechanisms of tool abrasive wear,grain breaking- off and micro-chipping. The defects of PCD tools,such as cracks and nonuniform of the structure,accelerate the grain breaking- off and micro-chipping,and the adhesive wear appeared during adhesive bond were produced and fell off.