Application of infra-red techniques to research on mechanical properties

Abstract

Infra-red techniques can serve as a new tool, particularly useful in materials science research work. This paper describes the available techniques for infra-red temperature measurement and thermography, and provides experimental data for some metals and alloys, obtained by infra-red sensing during deformation and fatigue processes. It is shown that conventional tensile data can be correlated with the change in infra-red radiation which occurs during tensile stressing. The temperature field of a metal undergoing elastic-plastic deformation can be calculated using finite element analysis; on the other hand, the thermoelastic effect on the metal can be shown by thermography. Infra-red techniques can be used to predict fatigue damage, to monitor crack propagation and to give the alarm in the event of fracture. Finally, the irreversibility of the infra-red emission from the metal can be used as a basis for non-destructive testing.