Fracture Toughness and Failure Behavior of WC-Co Composites by Fracture Surface Analysis

, 한동빈; , J.J Mecholsky Jr.; , 한동빈; , J.J Mecholsky Jr.

J. Korean Ceram. Soc. > Volume 26(5); 1989 > Article

Journal of the Korean Ceramic Society 1989;26(5): 645.

파괴표면분석을 통한 WC-Co복합재료의 Fracture Toughness측정방법과 Failure Behavior

Fracture Toughness and Failure Behavior of WC-Co Composites by Fracture Surface Analysis

한동빈 , J.J Mecholsky Jr.

Dept. of Materials Science & Engineering, The Pennsylvania State University

ABSTRACT

Specimens of WC-Co were indented to measure the resulting crack size and unindented samples were fractured in 3-point flexure to obtain the strength and to measure characteristic features on the fracture surface. Fracture toughness was determined using fractography and compared to those determined using identation techniques. We show that principles of fracture mechanics can be applied WC-Co composites and can be used to analyze the fracture process. The fracture surfaces were examined by scanning electron microscopy and optical microscopy. Characteristic feature observed in glasses, single crystals and polycrystalline materials known as mirror, mist, hackle, and crack branching were identified for these composites. We discuss the importance of fracture surface analysis in determining the failure-initiating sources and the failure behaviorof WC-Co composites.