Statistical analysis for the strength and thermal shock behavior of MoAlB

The statistical distribution for the strength as well as thermal shock behavior of high-purity MoAlB, fabricated via self-propagating high-temperature combustion synthesis with hot pressing (SHS/HP), was investigated. Among the statistical distribution models, the three-parameter Weibull (3P-Weibull) method exhibited the best fit for the flexural strength of MoAlB, with the primary error in the low-stress region. Notably, the 3P-Weibull modulus of MoAlB fell between those of typical metals and ceramics, aligning with the trends in fracture toughness and thermal conductivity. Its critical thermal shock temperature ranges from 100°C to 200°C. The introduced pores did not only enhance thermal shock resistance across the entire temperature range, but also result in an abnormal strength recovery above 1000°C, which suggests that pores play a significant role in the abnormal strength recovery after water quenching, in addition to the established explanations such as the formation of oxide layer and grain kinking.