When you heat treat something it is very hard and brittle, tempering means you let the material cool and then reheat at a very low temp for a certain amount of time.Charts can be found anywhere.This takes the brittleness out of the material.Annealing takes the material up to it's original heat treating temp and gradually brings it down so it is soft again. Normalising is when the material is heated above it's transformation range then air cooled.partStress relieving is heating the material to a certain temp and holding for certain duration it is also known as aging.