Heat treatment of cold formed dished ends

Yes, definitely there are key aspects about deciding what kind of heat treatment to carry on. You mentioned cold forming. Cold forming ends up with a product that has a strained structure, inherently with internal residual stress. Sometimes just does not matter. Sometimes its benefical Sometimes not, in your case, I bet you could have problems with residual stresses plus thermal induced tensions... Stress relief will not transform your structure, just allow these internal tensions to relieve (it is done below transformation temperatures). Normalizing is done by microstructure transformation, and is intended to obtain a more homogeneous structure, which is usually more refined because you did after the cold work and, thus, with reduced grain size. Good if you have subsequent work to do. Even better for toughness improvement and low temp leak-before-break characteristics. Ok, you asked for links. Instead of telling you details about what is stress relief and normalising, I will do better: go to an university or somewhere that has access to the worldwide known and save-my-neck-in-tight-situations publication called Metals Handbook. There are several different volumes. Look for heat treating of steel. A google search will also reveal you probably what you need to know. But, in these fundamentals of steel processing, I really believe that you will do better with a good book.