TABLE OF CONTENTS Accelerated life testing of products, components and materials is used to get information quickly on specific lives, life distributions, failure rates, mean lives and reliabilities. Accelerated testing is achieved by subjecting the test units to application and operation stress levels that are more severe than normal or use stress levels, to shorten their lives or their times to failure. If the results can be extrapolated to the use stress levels, they yield estimates of the lives and reliabilities under use stresses. Such tests provide a saving in time and expense since for many products, components and materials, life under use conditions is so great that testing under those conditions is not time-wise and economically feasible.
Accelerated test conditions are typically produced by testing units at higher levels of temperature, voltage, wattage, pressure, vibration amplitude, frequency, cycling rate, loads, humidity, etc., or some combination thereof, than are encountered under use conditions. The use of such accelerating variables for a specific product or material is dictated by experienced engineering practice. For example, if temperature is the only accelerating variable the Arrhenius Accelerated Test Model may be used. Then, life data obtained from units tested at different constant elevated temperatures are analyzed and extrapolated to obtain an estimate of the life and reliability at use temperatures. The Inverse Power Law Accelerated Test Model may be used to analyze accelerated life test data of insulating fluids, capacitors, bearings, electronic devices, and other products, to...
