薄板坯连铸连轧时夹杂物在奥氏体中形成与控制的理论考虑

Theoretical Consideration on Formation and Control of Inclusions in Austenite during Thin Slab Concasting and Continuous Rolling

根据奥氏体中第二相的固溶度积理论、Ostwald熟化理论、晶粒尺寸控制理论和沉淀强化理论 ,对薄板坯连铸 连轧时钢中主要夹杂物在奥氏体中形成的可能性及其尺寸的控制进行了理论分析计算。结果表明 ,硫化锰是有可能控制使之在奥氏体中以 10 0nm以下尺寸沉淀析出 ;而氧化铝夹杂在目前条件下很难使之完全在固态铁中析出。夹杂物在钢中控制再加热时奥氏体晶粒尺寸及产生沉淀强化效果的可能性的分析表明 ,固态铁中析出的硫化锰可有效抑制均热态奥氏体晶粒粗化并产生微弱的沉淀强化效果。

According to the solubility product theory of second phase in austenite, Ostward ripening theory, grain size control theory and precipitation strengthening theory, the probability for formation of inclusions in austenite and the inclusion size control have been theoretically analyzed and calculated. The results show that the manganese sulfide inclusion can be controlled to precipitate in austenite with size less than 100 nm while it is difficult at present condition for the alumina inclusions to completely precipitate in solid iron. It is obtained by analysis on the probability of control to reheating austenite grain size and producing precipitate strengthening effect by inclusions in steel that the manganese sulfide precipitated in solid iron can effectively prohibit austenite grain growth in heating and provide somewhat of precipitation strengthening effect.