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铁碳系统碳素钢为机械制造工程支撑用材,在共析钢中珠光体晶团内,铁素体层片位向为等同的,晶团属相变基本单元,同样在亚共析钢中,除部分珠光体外,其中等轴状先共析铁素体的组织结构为有序的,实质上,为一晶团。因此,铁素体晶团为铁碳系统碳素钢组织结构的基元结构,钢件力学性能受控于晶团。晶团解理等效于珠光体解理,反之亦然,最为凸显的是,所有晶团的统计尺寸,是6μm小尺寸的,这是必然的,解理断裂抗力反比晶团尺寸(N_a~(-1/2)),且与外界条件变化无关,诸如与外界温度变化无关,均为铁碳钢材至为珍贵特性。珠光体晶团结构为有序型的,珠光体的结构便亦为有序型的,认为珠光体的形成机制为无序扩散型的是错误的,其形成机制为有序型的。
Iron-carbon system Carbon steel for the machinery manufacturing engineering support material, in the eutectoid steel pearlite, the ferrite layer to the same bit, the crystal phase transformation of the basic unit, the same in the sub-eutectoid steel, In addition to some pearlite, in which the structure of equiaxed proeutectoid ferrite is ordered, essentially, a cluster. Therefore, the ferrite grains are carbon-carbon steel carbon steel structure of the basic structure, the mechanical properties of steel controlled by the crystal. Crystal cleavage is equivalent to pearlite cleavage, and vice versa, the most prominent is that all the statistical size of the crystal is 6μm small size, which is inevitable, cleavage fracture resistance antiparallel crystal size (N_a ~ (-1/2)), and has nothing to do with changes in the external conditions, such as iron and carbon steel is precious properties such as temperature changes has nothing to do with the outside world. The structure of pearlite is ordered and the structure of pearlite is also ordered. It is considered that the formation mechanism of pearlite is wrong and its formation mechanism is ordered.