Question: can there be down sides to working with space craft materials?

Hollie Heard answered on 12 Mar 2018:

There can be issues with particular materials for any application. It might be that you need specific metal that is quite difficult to get hold of or you need specialist training to handle or that you need mirrors perfectly polished to within fraction of a degree so that the images of distance galaxies aren’t fuzzy. The problem with the materials can also be making them resistant to the space environment and the extent of the testing needed to provide it. It can take years for a new material to be used on space mission, particularly manned ones, as if anything goes wrong they can pose a serious danger. That’s also partly one of the reasons why we try not to use nuclear power sources anymore as if there was an issue during launch it could result in a cloud of nuclear material that could span hundreds of miles. Some of the most difficult space materials to deal with can be ones that are part of the engine. The propellant can be extremely toxic or need large propellant tanks or to be kept at high pressures. The engines themselves can get extremely hot at well over 1400’C. The project I was working on for ESA was looking at applying a new coating to the thrust chamber such that this temperature could be even higher an increase the thrust of the engine. Some alternate propulsion systems can run at even higher temperatures so you may have to use ultra-high temperature ceramics or carbon based materials that require specialist machining and can be delicate to from and shape. You also have to make sure all the materials are kept clean and not contaminated in any way whilst they are built. The important thing is to be aware of all the issues when you are designing and choosing what materials to use so that you can try and minimise any problems you might face. I hope this hasn’t scared you off maybe being interested in materials science! If you want to know anything else, or about a specific material, please ask!