How can we accurately estimate the lifetime distribution of materials under accelerated stress conditions? This paper proposes a method for estimating the lifetime distribution at use condition for constant stress accelerated life tests, considering both extrinsic and intrinsic failure modes. It seeks to better understand the two types of test conditions. The ultimate goal is to help estimate what the lifetime distribution will look like at normal use. A mixture of two distributions is introduced to describe these failure modes, assuming that the log lifetime of each failure mode follows a location-scale distribution and a linear relation exists between the location parameter and the stress. An estimation procedure using the expectation and maximization algorithm is proposed, with specific formulas for the Weibull distribution obtained. Ultimately, the estimates and properties of the stress level are considered. Numerical comparisons with the masked data model are also performed. This research provides a valuable tool for reliability engineers and materials scientists seeking to accurately predict the lifetime performance of materials under accelerated stress conditions, aiding in the design and selection of durable and reliable materials for various applications.
Published in the International Journal of Reliability, Quality and Safety Engineering, this paper aligns with the journal's focus on advancing methodologies for reliability analysis and risk assessment. By proposing a method for estimating lifetime distribution under two failure modes, the paper contributes to the journal's mission of providing insights and tools for engineers and researchers seeking to improve the reliability and safety of engineering systems.
| Category | Category Repetition |
|---|---|
| Technology: Engineering (General). Civil engineering (General) | 2 |
| Science: Mathematics | 2 |