Integrated Thermal Conduction and Hardenability Laboratory Activity

Abstract

This paper describes an integrated laboratory project between separate heat transfer and machine design courses. The project was structured around a Jominy end quench hardenability test. Most of the students participating were simultaneously enrolled in both classes. In the heat transfer class, students were required to model one-dimensional, transient thermal conduction for an end quench geometry of 4140 steel. In machine design, students applied their theoretical temperature profiles to a continuous cooling transformation curve (CCT) of 4140 steel to predict microstructure and matched the theoretical cooling rates with hardenability curves from literature to predict hardness. In laboratory, students then performed an end quench test in accordance with ASTM A255 on four steel rods. By combining activities across the two courses, students developed an appreciation for the interconnectivity of material within the engineering curriculum, and learned that practical applications typically require they employ knowledge from a variety of sources.