Page 55 - Fundamental of Engineering Design
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Material classification


       Metal                                        Can be further divided into ferrous and nonferrous

                                                    alloys, ferrous alloy are based on iron, which has
                                                    mechanical properties. Nonferrous alloy are based

                                                    on material other than iron such as copper, tin,
                                                    aluminum and lead.


       Ceramic and glass                            These are result of the combination of metallic and
                                                    non-metallic element. they are good insulator,

                                                    brittle, thermally stable and more wear resistant
                                                    compare with metals. They are also harder and

                                                    lower thermal expansion than most metals

       Woods and organics                           These are obtained from trees and plant. Their

                                                    major advantages that they are a renewable
                                                    resource. However, some of their drawback include

                                                    that they absorb water, required special treatment
                                                    to prevent rotting and are more flammable


       Polymers and plastics                        These material change viscosity with variation in
                                                    temperature, easy told into given shape. Good

                                                    insulator , resistance to chemical and water,

                                                    smooth surface finish, available in many color
                                                    (eliminate painting), low strength, deteriorate in

                                                    ultraviolet light.                                                                 55
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