Fracture toughness testing for advanced technical ceramics: Internationally agreed good practice

Abstract

The development of robust methods for determining fracture toughness and for interlaboratory assessment of results is discussed with respect to procedural standardisation. Acceptable methods are based on meeting several criteria, including ease and cost-effectiveness of testpiece manufacture, the method of introducing a sharp precrack and the acceptability of appropriate fracture toughness analysis. The four simplest methods meeting these criteria are reviewed in detail, together with information on their reproducibility gathered during international round robin exercises. Not all these methods are effective on all materials, and users need to be aware of their limitations. Details of calibration equations and some experimental nuances are given.

Keywords

ADVANCED CERAMICS FRACTURE TOUGHNESS R-CURVE BEHAVIOUR ROUND ROBIN TESTS STANDARDISATION

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