Stress envelope of silicon carbide composites at elevated temperatures
Stress envelope of silicon carbide composites at elevated temperatures
复制标题
碳化硅复合材料在高温下的应力包络
DOI：
10.1016/j.fusengdes.2013.12.032
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
H. Tanigawa
中科院分区：
文献类型：
--
作者：
T. Nozawa;Sunghun Kim;K. Ozawa;H. Tanigawa
为了确定用于实际部件设计的碳化硅纤维增强碳化硅基复合材料（SiC/SiC复合材料）的综合应力包络线，即强度各向异性图，使用专门为高温使用定制的小样本测试技术进行拉伸和压缩测试。然而，面内剪切性能是使用离轴拉伸方法估计的，并假设混合模式失效准则（即 Tsai-Wu 准则）对于复合材料有效。初步测试结果表明，在低于 1000 °C 的温度下，拉伸载荷不会显着降低比例极限应力 (PLS) 或断裂强度。除了 PLS 略有下降外，在高温下也具有类似良好的压缩性能耐受性。根据拉伸、压缩和面内剪切性能的高温试验数据，最终得到高温下的应力包络线。当压缩模式占主导地位时，设计极限在高温下明显略有降低，而考虑到拉伸载荷情况，预计对设计的影响可忽略不计。
To identify a comprehensive stress envelope, i.e., strength anisotropy map, of silicon carbide fiber-reinforced silicon carbide matrix composite (SiC/SiC composite) for practical component design, tensile and compressive tests were conducted using the small specimen test technique specifically tailored for high-temperature use. In-plane shear properties were, however, estimated using the off-axial tensile method and assuming that the mixed mode failure criterion, i.e., Tsai–Wu criterion, is valid for the composites. The preliminary test results indicate no significant degradation to either proportional limit stress (PLS) or fracture strength by tensile loading at temperatures below 1000 °C. A similarly good tolerance of compressive properties was identified at elevated temperatures, except for a slight degradation in PLS. With the high-temperature test data of tensile, compressive and in-plane shear properties, the stress envelopes at elevated temperatures were finally obtained. A slight reduction in the design limit was obvious at elevated temperatures when the compressive mode is dominant, whereas a negligibly small impact on the design is expected by considering the tensile loading case.