涂层硬质合金基体特性及其对刀具失效机理的影响

涂层硬质合金刀具的推广应用越来越广泛。如何在选择好涂层材料的同时,合理选择基体材料,做到涂层和基体的良好匹配,这是涂层硬质合金刀具的生产者和使用者都普遍关心的问题。本文以目前切钢牌号涂层硬质合金刀具最常用的两类基体——钨钴钛类和钨钴钛添加钽(铌)类硬质合金作为典型代表,研究它们作为涂层硬质合金刀具基体时的性能特点,及其对涂层硬质合金刀具失效机理的影响;在试验资料和理论分析的基础上,指出了在不同切削条件下正确选用基体的方向,以及研究特殊基体的必要性和可能性。

EFFECT OF THE SUBSTRATE PROPERTIES ON THE FAILURE MECHANISM OF COATED CARBIDE TOOLS

Coated carbide tools are now playing a more and more important role in production engineering. It appears to be a problem, to both the makers and the users of coated carbide tools, how to optimize the selection of the substrate materials in accordance with the selection of coating layers. Taking as examples the cemented carbides varieties WC-Co-TiC and WC-Co-TiC-TaC (NbC) kinds, which are the very common materials as substrates of the coated carbide tools of steel cutting grades, this paper investigates the characteristics of their properties and their effect on the failure mechanism of coated carbide tools. Based on some test results and theoretical analyses,some priciples for the selection of substrate materials in specific cutting conditions are proposed. The necessity and possibility of the design of special substrate materials are also discussed.