I have been designing and building apparatus of all sorts since 1974, starting with food processing machinery, through cryogenics apparatus, through fuel cell stacks and systems, and on to my current position in a start-up company developing materials for lithium batteries, and other uses.
I realised about 20 years ago that every year I was doing more development of the materials that I was using to make things, to the point that I am now developing just the materials, and not the products they are used in.
So, I have come into materials development by the back door, as it were.
It is intriguing enough that I am going to recommend it as an interdisciplinary path for anyone who likes pure sciences and engineering, and is uncertain which to follow.
Currently it is central to developments in aerospace, biomedical advances, energy efficiency and recovery, and a multitude of other disciplines.