Experimental Investigation of the Internal Heating of Metals in a Wide Range of Strain Rates Using Simultaneous Digital Image Correlation and High Speed Infrared Imaging

Internal heating of plastically deforming materials has been studied quite extensively, in particular to determine the fractions of external work energy that are converted to heat or stored in the internal defect structure of the material. For the fraction of the energy converted to heat, the results from both theoretical considerations and experimental studies range widely from some tens of percent to full 100%, depending on the studied material, applied methodologies and experimental techniques, and assumptions and simplifications made in the calculations and manipulation of the experimental data. As recently many of the experimental techniques used in materials research have developed enormously, completely new possibilities for the research of the above mentioned questions now exist. In this work, the plastic deformation behavior and related thermal response of austenitic stainless steels were studied using simultaneous full-field digital image correlation and thermal mapping of the surface strains and temperatures of the specimens.