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<p>[QUOTE=&quot;physics-fan3.14, post: 2336888, member: 19165&quot;]I have never heard it called draft toning. I have always heard it called pull-away toning. There have been several people say that convincing AT&#039;d coins have been produced with pull-away, but I&#039;ve never seen it myself (and, when asked, they have been reticent to show proof). If anyone has a picture to show, I&#039;d love to see it. </p><p><br /></p><p><br /></p><p><br /></p><p>In an extreme case of work hardening, the metal become very brittle, as you describe. However, any time the metal is stressed, there is a certain amount of work hardening. If you think of how the coin is produced, the metal of the planchet &quot;flows&quot; (for lack of a better term) into the die. The movement in the metal produces a certain amount of work hardening around the devices. </p><p><br /></p><p>Work hardening is also a major concern in the production of dies (especially in the old double-squeeze system). The soft die steel was work hardened after the first impression of the hub, and then had to be annealed before the second impression. During the annealing process, the dies could warp. When the second impression occurred, all the details would be slightly off: this is the source of most hub doubling. Also, if the die was improperly annealed, it would wear quickly and you would get excessive die deterioration doubling.[/QUOTE]</p><p><br /></p>

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