by Michael G. Busch., Associate Editor Materials Engineering

Engineering materials are commonly defined and specified by their properties. And of all the properties a material may possess, mechanical properties often are the most important because virtually all fabrication processes and most service conditions involve some type of mechanical loading. Thus, in selecting materials you must know the mechanical properties of a material and what they stand for. As this glossary shows, there are literally hundreds of different mechanical properties and terms. And behind each property there generally is a test that defines the property and tells how to measure it. Thus, a large part of our "picture" of a material is based on the sum of its mechanical properties and tests for measuring these properties. Here is a summary of the properties, tests and terms you should know in order to make an intelligent choice of materials.