Administração cientifica

Simpósio Internacional de Confiabilidade Rio de Janeiro 2003

UNDERSTANDING ACCELERATED LIFE-TESTING ANALYSIS

Summary & Purpose

Accelerated tests are becoming increasingly popular in today’s industry due to the need for obtaining life data quickly. Life testing of products under higher stress levels without introducing additional failure modes can provide significant savings of both time and money. Correct analysis of data gathered via such accelerated life testing will yield parameters and other information for the product’s life under use stress conditions.

This is a brief introductory tutorial on this subject. Its main purpose is to introduce the participant to some of the basic theories and methodologies of accelerated life testing data analysis.

Introduction

Traditional “Life Data Analysis” involves analyzing times-to-failure data (of a product, system or component) obtained under “normal” operating conditions in order to quantify the life characteristics of the product, system or component. In many situations, and for many reasons, such life data (or times-to-failure data) is very difficult, if not impossible, to obtain. The reasons for this difficulty can include the long life times of today’s products, the small time period between design and release, and the challenge of testing products that are used continuously under normal conditions. Given this difficulty, and the need to observe failures of products to better understand their failure modes and their life characteristics, reliability practitioners have attempted to devise methods to force these products to fail more quickly than they would under normal use conditions. In other words, they have attempted to accelerate their failures. Over the years, the term “Accelerated Life Testing” has been used to describe all such practices.
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