Best explanation I can find of the annealing we do. Comments??? "Like most engineering terms, annealing is subject to interpretation depending on the processes being supported. For example, when making brass musical instruments, considerable stretching and working of the metal is required. Working the metal causes the grains to align, which make the metal stronger and more brittle. Stronger in that it will take more force to deform it, and more brittle in that it is more likely to crack with further working. With brass instruments, one anneals the metal to until it begins to glow, and then cooling it by whatever means works (brass cannot be heat-treated too make it stronger and the cooling method for this purpose doesn't matter). It's important to note that in this application, the brass is going to be burnished, rolled, hammered, or otherwise worked which will strengthen it after annealing. For brass that is not going to be further worked, annealing it to fully soft might ruin it for its intended application. Thus, brass is annealed to soften it to allow further working without causing it to crack. Annealing as a process may be performed to relieve internal stresses, but stress relieving isn't the same thing as annealing. Annealing may also be the first step in heat treating metal to make it harder, but heat treatment is not the same thing as annealing. And, heat-treating doesn't work for brass anyway--annealing destroys the grain structure that makes the metal stronger and quenching it does not restore that structure as it does, say, with steel." My annealing consists of getting the brass at the mouth end of the case just to the point of a dull glow in a darkened room and holding it for a few seconds followed by an air cool. I have lost some .17 Remington cases (radial separation at the shoulder) due to over annealing, but they were few. Hard to remain consistent on this small a case, but on large cases, never lost one in many many firing. Cary
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