Using hands-on laboratory experiences to underscore concepts and to create excitement about materials

It is universally acknowledged that laboratories and demonstrations add information and interest to science and engineering courses. Constraints are time, space and cost. We have developed a series of hands-on laboratories coordinated with our "Introduction to Principles and Properties of Materials" course, taken as a Basic Engineering elective by most of the engineering majors in the McCormick School of Engineering and Applied Science at Northwestern. These activities are conducted in 50-minute weekly sessions with approximately 40 students in each section. Our objective is for students to handle materials and to make qualitative observations and quantitative measurements. The experiments described herein are easily and inexpensively duplicated, allowing individuals or small groups to work independently. We describe the following representative activities in detail: the observation of work hardening and recrystallization in copper tubing; measurement of temperature-dependent resistivities of metals and semiconductors; exploration of the glass transition in inorganic and organic materials; measurement of LED I-V curves with a simple circuit; and quantitative determination of the effect of surface flaws on the strength of glass.