What is tempering? How does it work?

Question

I hear a lot about tempering when it comes to metal, glass and cooking (tempering chocolate or tempering custard)

What exactly is tempering? How do you do it? How does it work scientifically?

In: 2

Answer 1

Tempering steel is when you get it red hot. This rearranges the molecules in a way where they are more uniform. Suddenly cooling it rapidly freezes the molecules in that position. This makes the steel more pliableand loose but still hard enough to be effective as a tool or weapon. Without tempering there would be weak spots for the steel to shatter. Like a weak link in the molecular chain where a failure could happen.