ACCELERATED DURABILITY TESTING AND DATA ANALYSIS FOR PRODUCTS WITH MULTIPLE FAILURE MECHANISMS

摘要

Durability and reliability performance is one of the most important concerns of ground vehicle systems, which usually experience cyclic fatigue loadings and eventually fail over time. Creep and oxidation caused damages at elevated temperature conditions further shorten the life of a system and make the life assessment even more complex. One of the key challenges posed to design engineers is to find a way to accelerate the durability tests for products with multiple failure modes and to validate designs within development cycle to satisfy customer's and market's requirements. The accelerated testing procedures for products with single failure modes have been studied for several decades and essentially well established even though some fundamental issues are still unsolved. By contrast, much is needed to do for the accelerated testing procedure of products with multiple failure modes and their interactions. In this paper, a new accelerated testing and data analysis procedure suitable for products with linear homoscedastic data pattern is proposed. Examples related to durability life of high temperature components with single failure modes such as fatigue, creep, and oxidation are provided to demonstrate the procedure developed. Durability life assessment of components with multiple failure modes is also investigated and demonstrated with creep-fatigue and fatigue-oxidation damage analyses.