Effect of load reversals upon the growth rate of stable cracks in alumina
- Univ. of London (United Kingdom)
In this paper, the authors report some observation made during an investigation of the slow propagation of cracks under static loads in alumina. These observations show that a single unloading and reloading step, performed while the crack grows under a static load, is sufficient to produce a dramatic change in the crack growth rate. A notched and pre-cracked tapered double cantilever beam specimen of Vitox alumina of 8.1 {mu}m grain size was used in the experiment. These results support the conclusions reached regarding the effect of cyclic loads on the crack growth rate in alumina, namely that load reversals help to rupture the strong elastic ligaments existing mainly behind the crack tip, and that differences in crack tip mechanisms are responsible for the effect of loading mode (static versus cyclic) in the slow growth of cracks in alumina.
- OSTI ID:
- 69645
- Journal Information:
- Scripta Metallurgica et Materialia, Journal Name: Scripta Metallurgica et Materialia Journal Issue: 10 Vol. 32; ISSN SCRMEX; ISSN 0956-716X
- Country of Publication:
- United States
- Language:
- English
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