Investigating the Effects of Particle Modality and Morphology on the Hardness and Toughness of Tungsten Carbide Cermets
Abstract
Tungsten carbide ceramic particles can be bound in a ductile, metallic matrix to form a hard and tough cermet system. This cemented carbide has a vast potential application space, ranging from cutting tools to anti-armor penetrators, due to its unique combination of mechanical properties. It is well known that hardness and toughness have an inverse relationship, which, in this system, can be tailored through careful control of the binder phase content and ceramic particle size and morphology. However, there is a desire to surpass the tradeoff for these cermets and improve toughness, while maintaining hardness at a specific binder phase composition. Studies performed on similar materials have shown an increase in toughness can occur by altering the morphology and modal distribution of the particles. This study aims to examine this phenomenon with a goal of improving toughness (11 MPa-m1/2) without compromising hardness (15 GPa). Specimens of various bimodal and trimodal distributions, with different mean particle sizes, were fabricated and characterized. Hardness was measured through Knoop indentation and fracture toughness was measured via Palmqvist toughness tests. The effect of substituting spherical WC particles into these distributions was also evaluated. Ultimately, the goal of maintaining hardness and increasing fracture toughness was achieved.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2019
- Accession Number
- AD1080922
Entities
People
- Charles M Griffith
- John J. Iii Pittari
Organizations
- United States Army Research Laboratory