关键词: 真实环境应力, 可靠性评估, 加速模型, 加速寿命试验, 时变应力

Abstract: The traditional reliability evaluation methods only consider the product under constant stress. However, products are often directly exposed to the outdoor natural environment in actual engineering, and the working environment stress or storage environment stress varies with time. Aimed to solve this problem, the natural environmental stress of the typical geographical location is introduced, and the environmental stress variation tendency is derived by using six-parameter polynomial fitting method. Moreover, two modes of the time-varying environmental stress are assumed, and on the basis of Nelson cumulative damage model, the product reliability evaluation method based on accelerated life test data is studied under the real time-varying environmental stress. The results show that the reliability life of the products at different geographical locations is quite different, and the reliability of the products can be evaluated more accurately by introducing the real environmental stress of the geographical location of the product.

Key words: real environmental stress, reliability assessment, acceleration model, accelerated life test, time-varying stress