纳米硬质合金摩擦磨损与切削性能研究

摩擦磨损性能、磨削性能、切削性能对纳米硬质合金实用化具有极其重要意义。应用摩擦磨损试验机研究了纳米硬质合金WC-7Co和WC-10Co的摩擦磨损性能，利用在线电解修整（Electrolytic in Process Dressing, ELID）磨削技术对纳米硬质合金刀具进行了刃磨，并且对Al/SiCp复合材料进行了切削试验，研究了纳米硬质合金刀具的切削性能与刀具磨损机理。结果表明：纳米硬质合金整体摩擦系数低，耐磨性好，WC-10Co的磨损机理表现为鱼鳞状塑性流动；纳米硬质合金磨削加工性较好，磨削机理以塑性去除为主；纳米硬质合金刀具磨损机理为Al/SiCP复合材料中SiC颗粒对刃口断续冲击，其切削实质是断续切削，刀具磨损形式是刃口破损及晶粒脱落。纳米硬质合金刀具适于低速断续切削。

Friction, Wear and Cutting Performances of Nano Cemented Carbide Cutter

Performances, e.g. friction and wear, grinding and cutting, of nano-cemented carbides (WC-7Co and WC-10Co) are important for its development and potential applications. In this paper, the friction and wear of nano-cemented carbide was evaluated on a CJS111A tribo-meter. Cutting tests on Al/SiCP composite material using the nano-cemented carbide cutter sharpened by ELID (Electrolytic in Process Dressing) grinding were conducted to investigate its cutting performance and abrasive mechanism. The nano-cemented carbide cutter showed lower friction coefficient and higher wear resistance than that of common cemented carbide cutter. The abrasive mechanism of WC-10Co was characterized by fish-scale plastic flow. It was found that the nano-cemented carbide cutter had good grinding performance because the grinding mechanism was mainly contributed by plastic removal of material. An analysis of the used nano-cemented carbide cutter indicated that its abrasion mechanisms was cutting edge breakage and grain pull-out conducted by discontinuous impulsive force. The essence of cutting Al/SiCp is interrupted cutting. The nano-cemented carbide cutter was good for operation of interrupted cut at low speed.