Diffusion: Its not hard to understand once you see the mechanism in full (vacancies, interstials, etc) but its hard to write as txt. Suffice to say, there's p

Diffusion: Its not hard to understand once you see the mechanism in full (vacancies, interstials, etc) but its hard to write as txt. Suffice to say, there's plenty of room to squeeze. "Squeezing" When you squeeze you get rid of air bubbles, right? Well, when you squeeze you get rid of boundaries which are really volumes at small scales. Well nature hates surfaces, so if you squeeze surfaces close enough together and hot enough you'll give the material an opportunity to rearrange atoms to get rid of boundaries. "Ostwald ripening" If you thought sintering and diffusion are hard, I had a respected mechanical engineering professor working on a refractory materials project claim, when he first encountered it, that Ostwald ripening cannot occur. The mtls Eng guys rolled our eyes...