Observation of thermal strain on electronic packages using digital image correlation

Abstract

In this study, the thermal expansion of bi-metal specimen is measured by digital image correlation (DIC). A measurement system is developed for the evaluation of complex thermal strain distribution on electronic packages. A heating chamber is designed for applying the thermal load and DIC provides the full-field thermal deformation distribution of the bi-metal specimen due to temperature changes. The in-plane strain distribution measured by DIC is influenced by the out-of-plane displacement. By measuring the thermal expansion of the materials having known thermal expansion coefficient at same time, the effect of the out-of-plane displacement on the in-plane strain measurement is corrected. Experimental Results show that the thermal strain of the bi-metal specimen can be obtained by the measurement system including the out-of-plane displacement correction. © The Society for Experimental Mechanics, Inc. 2014.