碳含量对WC-Co硬质合金显微组织的影响及其控制

在硬质合金生产中,碳是影响硬质合金性能的关键因素,富碳时合金易出现游离石墨,缺碳时则易出现η相,这两种组织都会对合金的性能产生不利的影响,但即使合金处于正常组织,碳含量对性能也有很大的影响。文章对WC-Co硬质合金两相区的宽度、碳含量对其显微组织的影响以及在制备过程中如何控制碳含量进行了阐述。

Influence of Carbon Content on the Microstructure of WC-Co Cemented Carbides and Carbon Control

Carbon content has a strong effect on the microstructure and properties of cemented carbides. In the case of an excess of carbon,free carbon will be present in the structure causing porosity. If the carbon level is too low,η-phase forms which is a brittle and undesirable phase. Although the carbon content is within relatively close tolerance,the properties of cemented carbides are determined depending on the carbon content. In this paper,the range of carbon content of WC-Co and its influence on the microstructure are summarized. And how to control carbon content during the production is also illustrated.