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FRACTURE
Fracture occurs when a body is subjected to stresses and strains, which cause it to crack, leading the body to separate into two or more individual pieces. In this essay we will concentrate on fracture occurrence in Metals and alloys.
There has to be some sort of force acting on a material to make it fracture. ...
In engineering studies, there are two possible types of fracture, brittle and ductile{See Fig. ...
Brittle fracture is fracture that involves little or no plastic deformation. ... In brittle fracture, the cracks run close to perpendicular to the applied stress, there are certain characteristics in such fractures, for example: There is no permanent/plastic deformation of the metal in the region of brittle fracture. The surface of a brittle fracture is perpendicular to the principle tensile stress. There are also certain markings called chevrons, such as V-shaped marks and radial fan-shaped ridges near the center of the fracture cross-section {refer to Fig. ... Brittle fractures fall into different categories, such as transgranular fracture- where the fracture travels through the grain of the material. The fracture also changes direction from grain to grain due to random orientation of atoms in each grain. ... The second type of fracture is intergranular fracture. ... Intergranular fracture usually occurs when the phase in the grain boundary is weak and brittle ( i. ... Transgranular fracture cuts through the puzzle pieces, and intergranular fracture travels along the puzzle pieces pre-cut edges. Ductile fracture is quite the opposite; it is shown in [Fig. ... 2 shows the cup-and-cone fracture type. ... Here I will explain what tends to make a material tend to one form of fracture as oppose to another. ... Basically, at higher temperatures the yield strength is lowered and the fracture is more ductile in nature. On the opposite end, at lower temperatures the yield strength is greater and the fracture is more brittle in nature. ...
At moderate temperatures (with respect to the material) the material shows characteristics of both types of fracture. So to conclude, temperature determines the amount of brittle or ductile fracture that can occur in a material. ... One can determine if a material has failed by fatigue by looking at the fracture sight. A fatigue fracture will have two distinct regions; One being smooth or burnished as a result of the rubbing of the bottom and top of the crack; the second is granular, due to the rapid failure of the material.
Approximate Word count = 1956
Approximate Pages = 7.8
(250 words per page double spaced)
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