Durability tests allow validating the longterm durability performance of a product under physical and climatic hazards, which may occur during the product use. The goal of accelerated durability tests is to accumulate damage or failure in the shortest time by applying environmental stress levels and other conditions that are exaggerated beyond normal operating levels.
Durability is a characteristic of the product, expressed by the ability to function and meet its performance requirements under given conditions and for a stated time interval without exceeding acceptable failure levels.
If a product’s reliability is predicted inaccurately, there might be many recalls and complaints, high life cycle costs, as well as moneyand time-consuming maintenance. Durability tests are a main source of initial information for the prediction and need to be planned and performed properly under simulated environment.
Durability tests are usually performed as accelerated tests in order to reduce lead times in the development process. Accelerated testing is the process of testing a product in which conditions e.g., stress, temperatures, voltage, pressure etc.) are intensified in an effort to shorten the time to obtain a deteriorating effect, which is similar to the results from exposure to normal service conditions for a longer period of time (normally customer’s usage time).
Accelerated durability tests are necessary to provide recognition of compliance, analysis, and resolution of damage issues without extensive field tests. The combination of different types of accelerated tests (e.g., thermal, mechanical, electrical, etc.) assures a proper prediction of the product’s durability and guarantees that the product can meet its performance requirements.
Even if the use of accelerated tests might be dangerous because of the introduced uncertainties (e.g., complication of exposure conditions, extrapolating results to make predictions), it is generally unavoidable due to the increasing
competition for the development of new products in a short amount of time, which does not allow more realistic and time-consuming testing. As a result, it is very important to fully understand all product-affecting factors and how the accelerated test is related to the operating conditions. Depending on these specifications, the tests should be chosen appropriately, simulating the actual service environment and damage/failure mechanisms.
