Heat Treatment

Heat treat companion app Android | iOS
Heat treating basics
Heat treating procedure
Kevin Cashen heat treatment guidebook
Heat treating quick reference

Miscellaneous Metallurgy Resources

Metallurgy of Steel for Bladesmiths & Others who Heat Treat and Forge Steel by John D. Verhoeven | Mirror
Engineering Handbook (Contains lots of metallurgical goodness)
Melting temperatures of various metals
Shibuichi Alloying Calculator (Enter pour amount value, it does the rest. It is ratio based, so these are approximate values, mainly if you are using sterling instead of 999 silver. Make a copy of the sheet to your docs to edit.)
Comprehensive guide for metal etchants