[T15] Hard Materials

[16F-T15-01] Keynote: Microstructure Engineering to Improve the Performance of Hardmetals

*Z. Z. Fang¹ (1.University of Utah, USA)

キーワード：tungsten carbide, hardmetal, microstructure, functionally graded

The properties of any metallic alloys are dependent on their microstructure. Hardmetals are no exception. After 100 years, hardmetals are considered mature and it is thus implied that it is difficult to improve or change WC-Co in any drastic way. In this presentation, we discuss a few examples in which the performance, and sometimes the basic mechanical properties, of WC-Co materials are improved by designing unique and novel microstructures. These examples demonstrate that although carbide tools that will never wear nor break do not exist, there are opportunities to improve their performance. The examples include nano or ultrafine grain hardmetals, double-cemented tungsten carbide, cellular structured hard material composites, and the functionally graded WC-Co. The design of these different microstructures challenges the conventional debates regarding uniform microstructure versus bi-modal microstructure, fine grain versus coarse grain, and strength versus toughness. This presentation aims to contribute to these debates by sharing lessons learned.