Material is a substance which used in all work of engineering. There are more than 50,000 materials available to the engineer. The knowledge of materials and their properties are of great significance for a design engineer. The machine elements should be made of such a material which has properties suitable for the conditions of operation. In addition to this, a design engineer must be familiar with the effects which the manufacturing process and heat treatment have on the properties of the materials.
The engineering materials are classified as
b) Polymers: Polyethylene (PE), Polyvinylchloride (PVC), Nylon (PA), Natural rubber(NR) etc.
c) Ceramic & glasses: Alumina, Silica glasses & silicates, Silicon carbide, Cement &concrete etc.
d) Composites: Fiber glass (GFRP), Carbon-fiber reinforced polymers (CFRP) etc.
e) Natural materials: Wood, Leather, Cotton/wool/silk, Bone.The metals may be further classified as ferrous metals and non-ferrous metals.
The ferrous metals are those which have the iron as their main element, such as cast iron, wrought iron, steel, nickel etc.The non-ferrous metals are those which have a metal other than iron as their main element, such as copper, aluminium, brass, tin, zinc etc.
Difference between ferrous and non-ferrous metals
|Ferrous Metals||Non-ferrous Metals|
|Iron content is more.||Iron Content is missing.|
|The melting point is high.||The melting point is low.|
|This is of brown and black colour.||These are of different colours.|
|This catches rust.||This doesn't catch rust.|
|This can be magnetized.||This cannot be magnetized.|
|This is brittle in cold state.||This becomes brittle in hot state.|