【摘要】 本文对不同热处理条件下,低合金钢中由于原始组织不同而影响奥氏体晶粒粗化温度及混晶的现象进行了研究。采用了不同的固溶处理温度,改变原奥氏体晶粒的大小;采用了不同的冷却方式,获得不同的显微组织。从Gladman关于A1N粒子的临界半径公式出发,对原始奥氏体晶粒的大小、奥氏体平均晶粒尺寸和不均匀因子的作用进行了分析。并对于不同原始组织在从铁素体向奥氏体的转变中,奥氏体形核及奥氏体起始晶粒度对粗化温度的影响作了讨论。更多还原

【Abstract】 The effects of prior microstructure in steels 38Cr and 40CrNiMo formed by different heat treatments on the coarsening temperature and mixed grain of austenite were investigated. The solution treatment temperature was varied(850, 1200 and 1250℃) to vary the prior austenitic grain size; and the cooling method was varied (water quenching, oil quenching, furnace cooling, 450℃ or 650℃ isothermal treatment) to obtain different prior microstructure. Based upon the equation of the critical radius of AIN proposed by Gladman, the effect of prior microstructure on α→γ transformation, the effects of prior ausienitic grain size. the average austenitic grain size before coarsening and heterogeneity factor on the grain coarsening of austenite are discussed.更多还原