亚共析钢碳化物相的快速直接球化

依据作者关于钢中奥氏体晶粒尺寸影响相变产物中碳化物形态的观点， 本文分析研究了精轧过程中与碳化物球化有关的金属学问题； 指出在临界温度以下对过冷奥氏体实施精轧， 因铁素体“超量”析出而使奥氏体晶粒细化， 并随精轧形变量的增加， 在晶内诱发共析相变； 精轧后的钢继续在精轧温度短时停留， 可实现碳化物相的优良球化。

Rapid and Direct Spheroidization of Carbide in Hypoeutectoid Steels

Some phys metallurgical problems related to direct spheroidization of carbide in the process of fine rolling were analyzed and investigated in this paper in accordance with the author's viewpoint that the morphology of carbide phase in product of eutectoid reaction might be affected by grain size of austenite mother phase in steels. It is concluded that when a hypoeutectoid steel with super cooled mono phase austenite microstructure is fine rolled at the temperature bellow the equilibrium point of Ae1 in Fe C diagram, the austenite grains would be refined due to previous 'over precipitation' of ferrite along grain boundaries and deformation bands. At the same time, the eutectoid reaction of intra grains instead of that along the boundary is induced with the inerease of the rolling rate. While the as rolled steel stays briefly at the rolling temperature, carbide in the steel may be better spheroidized.