The strength of a material often is the primary concern. The strength refers to the ability of a structure to resist loads without failure because of excessive stress or deformation to cause appreciable plastic deformation or the maximum stress that the material can withstand. Universal strength and elongation tests are made on a wide range of materials including material’s ductility, which is a measure of how much it can be deformed before it fractures. Typical points of interest when testing a material include: ultimate universal strength or peak stress; offset yield strength which represents a point just beyond the onset of permanent deformation;
It specifies the test environment for determining the universal properties of moulding and extrusion plastics i.e. plastic strength specifications and covers the universal properties of unreinforced and reinforced plastics. These properties comprise of ultimate strength; strain at failure, and modulus. The mechanical properties of plastics can change dramatically when certain additives are included into the formulation. Some of these properties incorporate strength, ductility, and toughness. For the measurement of the speed of testing should be taken from the standard. This test method uses standard "dumbell" or "dog bone" shaped specimen under 14mm of thickness. A universal testing machine is required to perform this test. Measurement is made by using a universal tester applying a constant rate of elongation to the test strip. Universal strength is usually calculated in kN/m.
One of the properties you can determine about a material is its universal strength. This is the maximum load the specimen sustains during the test. The Universal Testing Machine may or may not equate to the strength at break. This all depends on what type of material you are testing; brittle, ductile, or a material that even exhibits both properties. And sometimes a material may be ductile when tested in a lab, but, when placed in service and exposed to extreme cold temperature, it may transition to brittle behavior.
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