materials in power electronics

I am a senior research fellow with the Power Electronics, Machines Centre at the University of Nottingham, where I’ve worked since 2007. My research over the past decade and a half has been primarily around materials science problems in power electronics converters. There’s an unfortunate, inherent paradox in the way power electronics works, in that the very property of semiconductors harnessed for energy conversion (they can be switched), also results in repeated heating and cooling. The trouble is that a power converter necessarily mandates a range of different materials to be assembled and interconnected to collaboratively provide electrical and thermal function. But these expand and contract at different rates! This makes reliability issues impossible to design out completely, and you’re never more than a micron away from a materials science problem! In my research, I probe and observe how these interconnected materials evolve and degrade when exposed to prolonged cyclical stresses, and produce experimental data to better understand component reliability, and to support the development of life prediction models. I sometimes get distracted by the beauty of cracks and pores, some observed by eye and others at length scales much smaller than the human. The processes and mechanisms of material degradation often seem to have a certain metaphorical quality.