Environmental influences in materials and technical systems and its simulation.

Technical products are affected during their service life by a number of environmental influences. These originate from both man-made natural sources. Such environmental influences include not only temperature, humidity and air pollution effects, but also those caused by mechanical shock and vibration, electromagnetic fields and biological attack by micro-organism. They all act together, some independently and some synergistically, to influence material properties, as well as functionability, service life, quality and reliability of the technical system. It is therefore technically and economically important to design and assemble products in a manner that will withstand the expected environment and perform as designed. A helpful tool in qualifying a technical product to survive in its expected environment is the concept of testtailoring. Reliable determination of cause-effect relationships between environmental loads and responses of the system provides the foundation for test-tailori ng. From these relationships one can derive environmental test procedures, whereby meaningful service life predictions may be made. Establishing such relationships, defining the environment, developing suitable test procedures, conducting laboratory evaluations and judging the results are the tasks of the environmental engineering specialist.