Plastic Tensile Test

The figure below from quadrant engineering plastic products shows the test geometry.

Plastic tensile test. Tensile testing of plastics supplies the data for a sample. Astm d638 is one of the most common plastic strength specifications and covers the tensile properties of unreinforced and reinforced plastics. In addition the use of direct extension measurement on the specimen is possible allowing informative stress strain diagrams to be generated. Separate tensile test methods are commonly applied to polymer films astm d882 or iso 1184 and elastomers astm d412 or iso 37.

This guide is designed to introduce you to the basic elements of an astm d638 plastic tensile test including an overview of the equipment software and samples needed. The test method can be used for testing materials up to 14mm 0 55 in and the material should be in the shape of a dumbbell or dog bone. Din en iso 527. A 5kn or 10kn 1125 or 2250 lbf system is most common but as reinforced plastics and composites increase in strength higher capacity units such as 30 or 50 kn systems may be required.

Tensile testing also known as tension testing is a fundamental materials science and engineering test in which a sample is subjected to a controlled tension until failure. For this test plastic samples are either machined from stock shapes or injection molded. The high speed tensile test can be performed using drop weight testers or hydraulic high speed tensile testing machines. This includes astm d638 technically equivalent to iso 527 1 is a testing standard which ascertains the tensile properties of a plastic material.

With the use of plastics being at an all time high it is critical that manufacturers be able to properly gauge the mechanical strength of their materials. The tensile testing machine. Pull off speeds up to 20 m s are achieved. From these measurements the following properties can also be determined.

Specimens are placed in the grips of the universal tester at a specified grip separation and pulled until failure. Astm d 638 tensile test procedure. Tensile tests are used for example in the validation of the chemical resistance of plastics since the results of this test disclose even extremely small changes in the material. The tensile test the test measures the force as a function of the strain being applied to the plastic sample.

Properties that are directly measured via a tensile test are ultimate tensile strength breaking strength maximum elongation and reduction in area. A universal testing machine tensile testing machine is needed to perform this test. A tensile test is typically governed via standards and the two most common in the plastics industry are astm d638 and iso 527.