Transient contact heat transfer measurements based on high-speed IR-thermography

Abstract

This paper presents measurements of transient contact heat transfer between specimens made out of several ferrous alloys for varying loads. The temporal resolution of the results allows for a deeper insight into the contact behaviour of the paired surfaces. At the same time, the application of high-speed infrared thermography increases the accuracy of the temperature measurements compared to the K-type thermocouples commonly used.The experimental data show a positive correlation between applied load and contact heat transfer, and the significance of the softer material's hardness, both agreeing with existing literature. With increasing load, the load-related gradient of contact heat transfer approaches zero, suggesting a limiting load, at which the maximum area of contact and therefore the maximum contact heat transfer coefficient is reached. In addition, the results suggest, that the transient approach allows for a post-experimental classification of the investigated contact.