engineering in action MATERIALS ENGINEERING AND Exploring Properties Crabtree Publishing Company www crabtreebooks com Robert Snedden
A WORLD OF MATERIALS We can see the work of materials engineers all around us Many industries rely on the expertise of materials engineers Civil engineers couldn’t design buildings aviation engineers couldn’t build aircraft and electronics engineers couldn’t make smartphones if it weren’t for materials engineers designing and testing the materials that go into each and every product Making things Every object we use is made of at least one material That’s what a material is something from which a thing can be made Materials in their natural state from which useful products are made are called raw materials Some raw materials just have to be shaped to make them useful such as stone for a building and wood to make furniture But most materials have had to be altered in some way Metals plastics and fabrics are all materials that have been processed from raw materials Metals are extracted from rock ores plastics are made from chemicals found in petroleum and fabrics have to be woven from natural and human-made materials Strength is an important characteristic of the materials we choose for building 4
Engineering the future Engineers are always looking for ways to improve materials Better materials make new technologies possible One of the most exciting things about materials engineering today is our growing ability to understand how materials are put together right down to the invisible level of atoms Materials scientists and engineers are focusing their efforts on changing the properties of materials by controlling their structure With this knowledge materials engineers hope to design new materials suited to perform any task Making the right choice So how do engineers know which materials are best for each job First they have to understand the properties of each material the qualities each one has that make it suitable for a particular use Materials and their properties affect every aspect of the things we use For example they affect cost reliability and how environmentally friendly they are Engineers generally follow an eight-step process when they are trying to design a solution to a problem Like all engineers materials engineers may not follow this process exactly but it generally guides their work Materials engineering researchers are always experimenting with new materials Steps in the design process Define the problem Identify criteria and constraints Brainstorm ideas Select a solution Build a model Improve the design Test the model Communicate the solution 5
