Synopsis
The objective of this experiment is to find out the different mechanical properties of General Purpose Polystyrene (GPPS), High Impact Polystyrene (HIPS), High Density Polyethylene (HDPE) and Polypropylene (PP). We obtained the average tensile strength, tensile modulus and yield strength of each specimens by using LLOYD tensile testing machine. We found out that GPPS specimens having the highest tensile strength and tensile modulus, and HDPE specimens having the lowest tensile strength, tensile modulus and yield strength. We also carried out the impact testing by using an Izod Impact Testing Machine. We found out that HIPS specimens having the highest impact strength and GPPS having the Lowest impact strength.
Introduction
In this experiment, we selected three specimens of each plastic materials such as General Purpose Polystyrene (GPPS), High Impact Polystyrene (HIPS), High Density Polyethylene (HDPE) and Polypropylene (PP). We used them to carry out tensile test and impact test. In the tensile test, we measured and recorded down the force required to stretch a specimen until it breaks.
In the impact test we ascertained the fracture characteristics of the specimens and used them to indicate the roughness of a specimen.
Theory
Tensile test tests a material's strength. It's a mechanical test where a pulling force is applied to a material until the specimen changes its shape and eventually breaks. It's is a common and important test that provides a variety of information about the material being tested, including the tensile strength tensile modulus, yield strength and yield point. Impact test tests the ability of the material to resist high-rate loading and also tests its impact strength. This determine the energy absorbed in fracturing a test specimen at high velocity. By measuring those changes, we can find out the mechanical behavior of the material, which reflects the relationship between its response...