`NASA cold welding research initiative`

The Mercury graphite-lubricant failure (knobs sticking in vacuum) motivated NASA to fund cold welding research, including the 1967 ASM conference and the *Adhesion or Cold Welding of Materials in Space Environments* volume Tom holds up.

What happened is they used graphite as the lubricant in the early Mercury space shots. When they went up into space and got down to very low pressures, like 10⁻¹⁰ atmospheres, you could strip the oxygen and CO₂ off the basal planes of the graphite. Now you have carbon bonds between the graphite particles, and those are very strong bonds. All of a sudden it was like putting diamond powder into your journal that's supposed to be a lubricant. The astronauts are up there, and the knobs are sticking, and all kinds of things are going wrong. Which is why we tended to just send people up as a little arc into the Atlantic. The Soviets, on the other hand, sent Yuri Gagarin up, and he got to take three trips around the earth before he came down. They didn't care as much. We sent up a dog first — or maybe they sent up a dog first. In any case, it's a different value of safety and risk in the two cultures.