The Hardness and Strength Properties of WC-Co Composites

• Published in: Materials Vol. 4; no. 7; pp. 1287 - 1308
• Main Author: Armstrong, Ronald W
• Format: Journal Article Book Review
• Language: English
• Published: Switzerland MDPI AG 14.07.2011; MDPI
• Subjects: Al2O3; cemented carbide; contiguity; cracking; dislocations; fracture stress; Hall-Petch relation; hardness; indentation fracture mechanics; MgO; Review; stress intensity; toughness; WC-Co composite; dislocations; stress intensity; indentation fracture mechanics; WC; Al2O3; cracking; hardness; Hall-Petch relation; MgO; cemented carbide; fracture stress; WC-Co composite; toughness; contiguity
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma4071287

The industrially-important WC-Co composite materials provide a useful, albeit complicated materials system for understanding the combined influences on hardness and strength properties of the constituent WC particle strengths, the particle sizes, their contiguities, and of Co binder hardness and mean free paths, and in total, the volume fraction of constituents. A connection is made here between the composite material properties, especially including the material fracture toughness, and the several materials-type considerations of: (1) related hardness stress-strain behaviors; (2) dislocation (viscoplastic) thermal activation characterizations; (3) Hall-Petch type reciprocal square root of particle or grain size dependencies; and (4) indentation and conventional fracture mechanics results. Related behaviors of MgO and Al₂O₃ crystal and polycrystal materials are also described for the purpose of making comparisons.