Part Durability and Life Limitation

The environmental effects on mechanical properties once again demonstrate that the interrelationships between various mechanical properties are material specific and rely on many factors, from temperature to humidity. A higher yield strength for one alloy under one environmental condition might imply better fatigue resistance however, specific supporting data are required to draw any inference to any other alloy in different circumstances. In summary, the demonstration of equivalent material durability and part life limitation in reverse engineering requires part-specific substantiation data. 

Consumers in more economically developed countries (MEDCs) have become accustomed to the availabihty of fashionable clothing that may not actually be used more than a handful of times before being discarded or unused. The development of this throwaway culture has been attributed in part to the success of the major value retailers and the increasing availability of high-street clothing at relatively low retail prices. At the end of life, opportunities for the reuse of such value clothing can be limited if it quickly goes out of fashion, or has poor appearance retention, dimensional stability, or durability. 

For a large number of plastics components, such as machine elements, pipes and vehicle parts, the problem of durability under dynamic load turns out to be the limit of service life lines under the influence of media, increased temperature, lubricants, climates and processing. Figure 1.62. 

---