论文部分内容阅读
钢中粗大晶粒使钢的屈服强度、塑性、韧性降低,尤其是使钢的脆性转变温度显著提高,降低零件可靠性。因此,人们力图使钢的晶粒细化。某些大型合金钢锻件易出现粗晶,与钢的组织遗传性有密切关系。钢的组织遗传性,主要指某些合金钢原始组织为粗大马氏体、贝氏体时,当重新加热到相变温度以上,在一定的加热条件(主要指加热速度)下,仍会获得粗大晶粒和断口,也就是继承了原始粗大奥氏体晶粒,包括位向、大小和形状。一些合金钢大锻件出现粗大晶粒和组织遗传性,这是大锻件生产特点所决定的。
The coarse grain in the steel reduces the yield strength, ductility and toughness of the steel, and in particular, significantly increases the brittle transition temperature of the steel and reduces the reliability of the part. Therefore, people try to refine the grain of steel. Some large alloy steel forgings prone to coarse grain, and the genetic organization of steel are closely related. The genetic organization of steel, mainly refers to some of the original alloy steel coarse martensite, bainite, when reheated to above the phase transition temperature, under certain heating conditions (mainly refers to the heating rate), will still be obtained Large grains and fractures, that is, inherited the original coarse austenite grains, including the orientation, size and shape. Some large alloy forgings appear coarse grain and organizational heredity, which is determined by the production characteristics of large forgings.