This is 'The Year When Stardust Fell'"The Year When Stardust Fell" by Raymond F. Jones, from 1958. One of the Winston series of YA books.
The menace in this story consists of dust from the tail of a comet. It consists of a colloid, analogous to smoke, that incorporates an unknown transuranic element. That element has a great affinity for metal surfaces and it weakens their surface tension, thereby enabling rapidly moving parts to cold weld themselves into solid rigidity.
