干车削奥氏体不锈钢硬质合金刀具磨损实验研究

Experimental Study on Wear of Carbide-Tipped Tools for Dry Turning Austenitic Stainless Steel

针对刀具在车削过程中磨损造成的快速失效问题,采用WC-Co硬质合金刀具进行奥氏体不锈钢干式车削实验,采用切削速度、进给量及背吃刀量为单一变量进行单因素实验,通过超景深三维显微镜观察刀具的磨损形貌,分析WC-Co硬质合金刀具的主要磨损机理及磨损形式。结果表明,WC-Co硬质合金刀具加工奥氏体不锈钢时,进给量、切削速度、背吃刀量对刀具寿命的影响依次减小,进给量越大,刀具磨损、崩刃现象越严重,刀具前刀面的月牙洼磨损随进给量的增加而急剧增大。刀具在磨损过程中依次经过初期轻磨损、中期稳定均匀磨损、后期剧烈快速磨损三个阶段。刀具的磨损机理主要为黏结磨损、氧化磨损、边界磨损。

In view of the rapid failure caused by tool wear in the turning process,WC-Co cemented carbide tool was used for turning of austenitic stainless steel under non-liquid cooling conditions.In this paper,the single factor experiment was carried out with the cutting speed,feed rate,and back cutting depth as single variables.The wear morphology of the tool was observed by the ultra-depth field 3 D microscope,and the primary wear mechanism and wear form of WC-Co cemented carbide tool were revealed.The results showed that when WC-Co cemented carbide tool was used to process austenitic stainless steel,the influence of feed rate,cutting speed,and back cutting depth on the tool life decreases in turn.The higher the feed rate,the more serious the tool wear and edge collapse.The crescent-depression wear of the rake face has a sharp increase with the increase of feed.In the process of tool wear,there were three stages:light wears in the early stage,stable and uniform wear in the middle stage,and severe and rapid wear in the later stage.The wear mechanism of the tool was mainly bond wear,oxidation wear,and boundary wear.