Monday 23 December 2013

PROBLEM 11.3 : MATERIALS SELECTION




Function of Design
Material Properties
1.    Strength in bending
-       Strengthness - The ability of a material to stand up to forces being applied without it bending, breaking, shattering or deforming in any way.
-       Is defined as a material's ability to resist deformation under load. The transverse bending test is most frequently employed, in which a rod specimen having either a circular or rectangular cross-section is bent until fracture using a three point flexural test technique. The flexural strength represents the highest stress experienced within the material at its moment of rupture.
2.    Resistance to twisting
-       Hardness - the property of a material to resist permanent indentation.
-       Strengthness - The ability of a material to stand up to forces being applied without it bending, breaking, shattering or deforming in any way.
3.    The ability of a sheet material to be stretched into a complex curvature
-       Elasticity-ability of a deformed material body to return to its original shape and size when the forces causing the deformation are removed.
-       Ductility-is a solid material's ability to deform under tensile stress; this is often characterized by the material's ability to be stretched. Forming by using tensile forces to stretch the material over a tool or form block, required materials with appreciable ductility.
4.    The ability to resist fracture from cracks at low temperatures
-       Fracture toughness is a property which describes the ability of a material containing a crack to resist fracture
-       Is a form of thermal cracking and results from a single drop in temperature to an extreme low, below the fracture temperature of the material.
-        

5.    The ability to resist shattering if dropped on the floor.
-       Toughness is the property that enables a material to withstand shock and to be deformed without rupturing.
-       The act of violently breaking into small pieces.
6.    The ability to resist alternating cycles of rapid heating and cooling
-       Thermal shock resistance- material's ability to withstand rapid changes in temperature.
-       Is a technique that is used to improve the surface quality of a part, while keeping the cycle time as short as possible.

Saturday 14 December 2013


Assignment #7.1 
Decision for whether to take an umbrella when going on work on cloudy day

The decision tree on whether to take umbrella or not during the cloudy day