Colin Humphreys: What is a Materials Scientist?

I'm Professor Sir Colin Humphreys. We're in the Department of Material Science and Metallurgy right in the centre of Cambridge and I'm a material scientist and I direct research in this department. Material scientists works on all solid materials. I've just got a range of them to show you here. So for example this is a turbine blade made out of 18 different elements which is flying in Rolls-Royce planes or something like this is flying in Rolls-Royce planes. Material scientists also work on magnets. Here's a couple of magnets which attract each other. This is a high temperature superconductor so we work on those. We work on biomaterials. So this artificial hip was made by a material scientist and also this polymer cap which fits into your pelvis was made by material scientists. We also work on light emitting materials. So this toy, this cow, the LED in here is bright light made by material scientists or even brighter lights. I won't shine it directly at the camera. Even brighter lights like this made by material scientists and this is a ceramic knife. So ceramic materials, this knife will never go blunt, always stay sharp and even the what's called the lead in a pencil, this giant pencil, this is graphite in here and a single layer is graphene which has been in the news a lot recently. So material scientists work on graphene as well. So material scientists work on all solid materials. Metallurgy is arguably the oldest science of them all. So it started with the bronze age and the iron age. It goes back to ancient Egypt and before and people then were learning by trial and error and so they had large numbers of people who could add elements and different elements and they learned to refine gold and so on. And for many, many years we were just doing things ourselves by trial and error and metallurgy was just metals and adding other elements to make alloys. But then when the electron microscope came along, we could see the internal structure of these materials. We could see if we added one element to another element, where that other element was going and we could start to understand what was happening. So electron microscopes enabled our understanding and basically what has happened now is that ancient metallurgy as it were has come into modern material science. So we no longer just look at metals and alloys, they're still very important, but we also look at a range of other materials. Semiconductor materials, ceramic materials and so on. And metallurgy also and material science now combines various disciplines. So it's like a bridge and on one side of the bridge material science sits on the pillars of physics, maths, chemistry, biology and on the other side of the bridge it sits on the pillar of engineering. And material science is often called an enabling technology because it enables you to cross this bridge so you can go from the basic sciences through to exploitation and then exploit an industry. So it's a really important subject now. In the past we just took what nature presented us with and we slightly modified it and improved it. Today we can design materials which don't exist in nature at all.