Elastic Vs Plastic Deformation

I. Definitions

In today's research, we will talk about the difference between Elastic and Plastic deformation. First off, we shall give the definition and concepts of Deformation itself. Deformation is the changes in the shape or size of a material due to many factors:

● an applied force, like tensile, compression, shear and bending forces.

● Temparature

The consequences of ground deformation can never been underestimated, severe deformation can lead to failure of structures and cause many casualties and chaos. Because of the severe deformation, there are many issues that can be raised, such as, the interruption and change of boundaries, causing problems to structures, ground sinks and destruction of structures and cause injuries and casualty.

With the notable exception of iron, metals tend to have a high degree of ductility, or to be deformed beyond their elastic limits without being ruptured. The ratio of tension to elongation for metals is high: in other words, a high amount of tension produces only a small amount of elongation while beyond the elastic limit the ratio of tension elongation is much lower. Because of their ductility they are capable of experiencing mechanical deformation through metallurgical processes, such as rolling, extrusion and others. Cold extrusion uses the application of high pressure to a metal without heating it, and is used on materials such as copper, tin, and zinc to change their form while Hot extrusion, involves heating a metal to a point of extremely high malleability, and then reshaping it. Metals may also be melted for the purposes of casting, or pouring the molten material into a

Ductile metals like gold, copper and silver have a large plastic deformation range. Hard thermosetting plastics like rubber, crystals and ceramics have minimal plastic deformation ranges.

Under tensile stress, plastic deformation is characterized by necking region and finally, fracture, which is also called rupture. Plastic deformation unlike on Elastic, includes the breaking of a limited number of atomic bonds by the movement of dislocations. However, the movement of dislocations allows atoms in crystal planes to slip past one another. The energy required to move is lowest along the densest planes of atoms, dislocations have a preferred direction of travel within a grain of the material. This results in slip that occurs along parallel planes within the grain. These parallel slip planes form together to form slip bands, which can be seen with an microscope.

Heat and pressure are the methods used to shape objects into the desired form. Speed of stress causes rapid material changes, and unable to take the pressure, the materials may break. Plastic deformation used in the manufacture of goods involves carefully controlling heat and pressure that allows the structure of the material to adapt slowly to the new nature and carefully bending until the preferred design and form is