Effect of tensile stress on thermal fatigue life of ZrB2-SiC-graphite composite

Publication date: 15 July 2017
Source:Materials & Design, Volume 126
Author(s): Xiaosheng Chen, Xianghe Peng, Zhen Wei, Xing Yue, Tao Fu
The thermal fatigue life of ZrB2-SiC-graphite composite under tensile stress of σ0=30, 40, 50 and 60MPa respectively was investigated, in which a newly developed approach was used to obtain the surface temperature distribution of the specimen. In each test the specimen was subjected to thermal cycles between 25°C and 2000°C under constant σ0. It was found that, with the increase of σ0, the thermal fatigue life decreases remarkably, accompanying different types of microcracks and different fracture morphologies. It was inferred that under smaller σ0 fracture may take place due to the coalescence of a lot of small microcracks, while under larger σ0 the specimen could possibly fracture due to the continuous propagation of large microcracks. The thermal fatigue life subjected to thermal cycles between 25°C and 2200°C under different σ0 was also tested, and the results showed the extremely low thermal fatigue life.

Graphical abstract

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