Planning Accelerated Life Tests With Two or More Experimental Factors

Accelerated life testing is a widely used tool for assessing the reliability of product components and materials. Most of the available literature on accelerated life testing deals with tests that use one accelerating factor and no other explanatory variables. Frequently, however, there is need to use more than one accelerating or other experimental factor. In this article we describe methods and guidelines for planning two-factor accelerated life test experiments for models in which there is no interaction between the factors. Although our discussion and examples focus on two-factor experiments, the extension to multifactor experiments is straightforward.