Went through a first round where they asked some straightforward questions about my previous experience and some basic mechanics of materials problems such as bending beam/static failure. I believe they opened it up for questions first. The first round interview was pretty short. For the second round, they asked me to explain my experiences and then asked some more general, theory-based questions such as materials-related things to consider when designing a product and some stress-strain curve questions. Was instantly rejected after the second round but there would've been one more round.