一、导言鋼材在热加工过程中,不仅鍛造、淬火可以引起裂紋,而且回火、校直、渗炭,甚至搬运不当心也都有造成开裂的危險。这种种裂紋往往不一定在形成以后就被发現,例如鍛造裂紋有时要在退火、淬火后才能暴露出来;而某些微細的淬火裂紋,則通常要在回火噴砂以后,甚至在磨削的过程中方能发觉。当然,有时还可能有原材料原有的残余裂紋夹杂在里面,以致对廢品分析工作的进行带来不少的困难。 First, the introduction of steel in the thermal processing, not only forging, quenching can cause cracks, but also tempering, straightening, charcoal, and even handling are not careful also have the risk of cracking. These kinds of cracks are often not necessarily found after they are formed. For example, forged cracks are sometimes exposed after annealing and quenching. Some fine quenching cracks are usually obtained after tempering, even after grinding The process can be found. Of course, there may be times when the original residual cracks in raw materials are mixed in, which brings many difficulties in the analysis of waste products.