摘要
针对一种低碳Si-Mn-Mo系贝氏体钢,研究了Si含量对过冷奥氏体连续冷却转变动力学曲线的影响,并用渗碳法测定了不同含Si量的钢中碳原子在奥氏体中扩散能力的大小。结果表明:(1)提高Si含量,钢的高温先共析铁素体析出C曲线左移,而中温转变(包括粒状贝氏体和粒状组织)C曲线右移;(2)在高温区,因Si可提高碳的活度从而增加碳原子在奥氏体中的扩散系数。在中温区,因Si可增加Fe原子的结合力而可提高碳原子扩散的激活能,从而可减小碳在奥氏体中的扩散系数。本文中对上述结果从理论上进行了分析。
This paper deals with the influence of silicon content on the continuous cooling transformation dynamics of undercooled austenite in low carbon Si-Mn-Mo bainite steels. The diffusivity of carbon in austenite in the various silicon content steels are studied by carburization. The results show that: (1) as the silicon content in the steels increasing,the CCT-curve of proeutectoid ferrite at the higher temperature shifts to the left and the CCT-curve of the immediate transformation tends to the right; (2) the diffusion coefficient of carbon in austenite is increased at higher temperature because of silicon improving the activity of carbon. And the diffusion coefficient is decreased at lower temperature because of silicon increasing the combining force of iron atom and increasing the diffusion activation energy of carbon atom.
出处
《金属热处理》
CAS
CSCD
北大核心
1992年第8期3-7,共5页
Heat Treatment of Metals
