Two Processing Structure Property Laboratory Activities To Culminate A Course In Engineering Materials

Most engineering students are required to take a course which focuses on Engineering Materials. A common theme of these courses is that Processing affects Structure which in turn affects Properties which ultimately determine Performance. Two laboratory sessions have been developed which demonstrate this principle: TTT Diagram Evaluation and Evaluation of Strengthening Mechanisms. To complete the TTT Diagram Evaluation laboratory the students evaluate the hardness and microstructure of heat treated 1080 steel samples. Heat treatments include heating below the austenite transformation temperature, heating above the austenite transition temperature and then cooling at elevated temperatures, and tempering martensite at various temperatures. The students then compare their results to those predicted by either the TTT diagram or coarsening theory. The Evaluation of Strengthening Mechanisms laboratory assignment requires that the students evaluate grain/particle size reduction, second-phase particle strengthening, solid solution strengthening, and work hardening. This is done by subjecting copper, single phase brass, and two 10 series steel alloys to various heat treatments, including forming martensite. The students perform a tensile test to evaluate the yield strength and ductility and take micrographs of the alloys.