Dan’s Other Job

During the day I have the best job ever. I get to work with a team of bright, enthusiastic people solving problems for folks around the world. We create jobs across the globe. From plutonium to potatoes, from oil to medicine with some rockets and racecars sprinkled in for good measure. This is all well and good, but work only lasts for part of each day. I tell folks that hyperactivity is a blessing, not a curse. And those of us blessed with this affliction need constant challenges.

My latest adventure involves building a portable heat treatment machine as a learning aid for a metallurgy class I assist with at the local community college. Our local community college has an abundance of buildings and administrators but lacks laboratory demonstration equipment. So I built a portable machine and took it into the classroom to teach the students. Heat treatment of steel is an essential technology in industry. To learn it properly, you need to understand the underlying principles of heating, cooling, crystalline structure, and chemistry. Benjamin Franklin once said: “Tell me and I forget. Teach me and I remember. Involve me and I learn". I think Ben may be on to something. 

To demonstrate how to heat treat steel, my machine heats piano wire using resistance heating, then cools it quickly (quenches) in water. The change in material properties is dramatic. I go into the concept of allotropy or the existence of two or more physical forms of an element. In the case of iron, the structure is body-centered cubic (BCC) at room temperature and face-centered cubic (FCC) at elevated temperatures. When iron is heated and transformed into FCC it becomes paramagnetic, the solubility of carbon goes up 10X, and it actually shrinks due to increased packing density. These concepts are not academic, they are essential to understanding the process. My machine demonstrates these changes and the resultant changes in mechanical properties. I hope you enjoy our video. Heat Treatment of Steel Class Video