无粘结相WC硬质合金的研究进展

Research Progress of Binderless WC Tungsten Carbide

无粘结相WC硬质合金(Binderless tungsten carbide,BTC)是WC硬质合金领域的研究热点,BTC具有较高熔点及良好的耐腐蚀性,与WC-Co等金属作为粘结剂的WC硬质合金相比,更适宜应用于高温、腐蚀性强等恶劣环境中。同时,BTC还具有高硬度以及良好的耐磨性等优异性能,是具有应用潜力的硬质合金材料。但是,其致密化温度高,采用传统的烧结方法很难使其致密化,在烧结过程中易发生晶粒异常长大,韧性较低。因此,一些研究人员将金属碳化物、金属氧化物以及碳材料等非金属添加剂加入其中,用于改善BTC的烧结性能、抑制烧结过程中的晶粒长大现象以及改善其力学性能,相关研究已经取得了一定进展。本文从BTC材料的分类、性能、制备方法、应用等方面对BTC的相关研究成果进行综述。在BTC分类中主要介绍不同陶瓷结合剂的添加对其性能的影响,对比了不同种类的BTC的性能差异,介绍了制备BTC材料常用的传统及先进的烧结技术。

The binderless WC tungsten carbide(BTC)which free of any metallic binder is the research focus in the field of WC cemented carbide.Owing to its high melting point,high hardness,good corrosion resistance and superior wear resistance,BTC has broad application prospect.It is more suitable for application in high temperature,strong corrosion and other harsh environments than traditional WC-Co cemented carbide and other WC cemented carbides with metallic binders addition.However,BTC is difficult to densified completely by traditional sintering method because of high densification temperature and abnormal grain growth during the sintering process.Besides,BTC has a lower value of toughness.Therefore,metal carbide,metal oxide and carbon materials have been added to BTC to inhibit grain growth during sintering and improve its sintering properties and mechanical properties in a lot of works.In this paper,the research progress in classification,properties,preparation methods and applications of BTC materials are reviewed.The influence of different ceramic binders on the properties of BTC is mainly introduced and the performance of different kinds of BTC is compared.Moreover,the traditional and advanced sintering technology commonly used to prepare BTC material is introduced.