Measurement of Temperature Increment in Compressive Quasi-Static and Dynamic Tests Using Infrared Thermography

During the plastic deformation of metals, part of the mechanical energy is retained in the material as plastic deformations and the rest is converted to heat. A temperature increment is a measure of the heat energy generated in the tested specimen. This temperature can be detected by measuring the infrared (IR) radiation emitted by the specimen surface. This study describes an attempt to improve the experimental procedure using IR thermography to measure the temperature increment as a function of the plastic strain of the studied materials. Tests were carried out under quasi-static and dynamic load conditions (using a universal testing machine and a Split Hopkinson pressure bar). The method is applied on an Al alloy (Al6082), a Mg alloy (ZC71) and the same Mg alloy reinforced with ceramic particles (SiC, 12 vol%). The emissivity measurement of the studied materials is detailed, as well as the method of synchronising the IR camera with the testing machines. Finally, the influence of test conditions on the measured temperature is analysed.