Interval Reliability Analysis of Titanium Alloy Fatigue

Benyang Tu, Chunyang Zhao

The fatigue crack growth process of titanium alloy is affected by uncertain factors, which leads to uncertainty in the parameters of fatigue analysis, and it is necessary to carry out reliability analysis. Aiming at the limitations of the probabilistic reliability method on the high sample size and statistical information and the large computational complexity, a non-probabilistic reliability analysis method for fatigue crack growth interval of titanium alloy is proposed. The uncertain parameters in the Paris model are expressed as intervals, the interval non-probabilistic reliability index of fatigue crack propagation is defined and considered based on the fatigue life model characterizes, and uses the interval mathematics theory to solve the non-probabilistic reliability index. The example calculation results show that the non-probability reliability index decreases linearly from 99.231% to 90.846%, and the calculation result is more conservative than the probability reliability method, which is safer in engineering applications.

https://dx.doi.org/10.31873/IJEAS.6.6.2019.07