※ 引述《kevin8290 (泰国王)》之铭言： : 原文吃光光 : 小弟刚好也有个退火的问题 : 藉由这标题上来请教一下 : 冷作之工件为消除应力，可施以（Ａ）弛力退火 （Ｂ）回火 : （Ｃ）制程退火 （Ｄ）应变硬化 : 此题是一本高职 机械制造 课本後面的练习题 : 根据课本内容，直觉答案是（Ａ），不过正确答案是（Ｃ） : 扫瞄课本内容如此连结 http://i.imgur.com/0JSYeMT.png : 难道是答案给错了？ : 还是要用更细微的探讨才能解此题？ 个人觉得其实是题目叙述不好所造成的误会 因为如果是消除应力选A或C都对 弛力退火(应力消除退火)是用材料在塑性变形完後所作的热处理 制程退火是在冷作制程中，为了避免加工硬化造成材料破裂， 因此施以热处理软化材料并回复材料的延展性後，继续冷作制程 所以要是将题目改为 [冷作制程中为避免加工造成应力断裂所施以的热处理?] 就比较不会有争议....... 为了避免小弟的认知错误， 补上原文 Process Annealing is used to treat work-hardened parts made out of low-Carbon steels (< 0.25% Carbon). This allows the parts to be soft enough to undergo further cold working without fracturing. Process annealing is done by raising the temperature to just below the Ferrite-Austenite region, line A1on the diagram. This temperature is about 727 ºC (1341 ºF) so heating it to about 700 ºC (1292 ºF) should suffice. This is held long enough to allow recrystallization of the ferrite phase, and then cooled in still air. Since the material stays in the same phase through out the process, the only change that occurs is the size, shape and distribution of the grain structure. This process is cheaper than either full annealing or normalizing since the material is not heated to a very high temperature or cooled in a furnace. Stress Relief Anneal is used to reduce residual stresses in large castings, welded parts and cold-formed parts. Such parts tend to have stresses due to thermal cycling or work hardening. Parts are heated to temperatures of up to 600 - 650 ºC (1112 - 1202 ºF), and held for an extended time (about 1 hour or more) and then slowly cooled in still air. --

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