摘要汽车的轻量化，是节能减排的一个重要指标，因此如何使汽车达到轻量化的同时不降低其性能成为当前研究的热点。高锰TWIP钢是非常有发展前景的汽车用钢，它具有高强度､高塑性､高应变硬化率和高能量吸收能力，可以在提高汽车轻量化的同时缓解碰撞时产生的冲击，因此研究高锰TWIP钢已然成为研究汽车轻量化课题的重要内容。本研究主要围绕高锰TWIP钢冶炼过程中涉及的去碳保锰反应中MnO的活度问题展开研究，采用化学平衡法获得银液与CaO-SiO2-MnO-FeO-MgO系不同FeO浓度的熔渣在CO+CO2混合气体条件下达到平衡时的[Mn]和渣中组分的平衡浓度，从而获得渣中MnO的活度系数和活度，研究FeO对渣中MnO的活度和活度系数的影响。实验结果表明：MnO活度系数与FeO摩尔分数呈非线性回归关系：61793

随着FeO摩尔分数的增加，MnO的活度系数及活度也逐渐增加，当FeO的摩尔分数增加到一定值时，MnO的活度逐渐减小。

毕业论文关键词：汽车轻量化；高锰TWIP钢；活度系数；化学平衡法

 Abstract The lightweight of automobile is an important index of energy saving and emission reduction, so how to make the automobile lightweight without reducing its performance has become a hot spot in the current research. High manganese TWIP Steel is very prospect of automobile steel, it has high strength and high plasticity, high strain hardening rate and high energy absorption ability, can be produced in improving auto lightweight and collision mitigation impact. Therefore, the study of high Mn TWIP Steel has already become the important content of the research of automotive lightweight task. This research mainly focus on high Mn TWIP Steel smelting process involved to carbon protection reaction of manganese MnO activity issues and use chemical equilibrium method was used to obtain the liquid silver and CaO-SiO2-MnO-FeO-MgO lines of different concentration of FeO slag reached balance in CO+CO2 mixture [Mn] and slag constituent equilibrium concentration, so as to obtain the activity coefficients and activity of MnO in the slag, FeO study of MnO in the slag activity and activity coefficient. The experimental results showed that the MnO activity coefficient and the FeO mole fraction showed a nonlinear regression relationship:

 With the increase of FeO mole fraction, the activity coefficient and activity of MnO increased gradually. When the mole fraction of FeO increased to a certain value, the activity of MnO decreased gradually.

KeyWords:Automobile lightweight; High manganese TWIP steel;Activity coefficient; Chemical equilibrium method 

目  录

1 文献综述 1

1.1 TWIP钢的研究现状 1

1.1.1 TWIP钢的层错能研究 1

1.1.2 TWIP钢浇铸与轧制研究 2

1.1.3 TWIP钢的强化机制研究 2

1.1.4 TWIP钢的延迟断裂行为研究 3

1.2 TWIP钢的力学性能与微观组织 3

1.2.1 力学性能 3

1.2.2 断口形貌分析 4

1.2.3 显微组织 4

1.2.4 钢板织构的测量 6

1.3 活度､活度系数和活度的测量方法 6

1.3.1 活度和活度系数 7

1.3.2 化学平衡法测活度 7

2 研究内容及研究的目的意义 10

2.1 课题研究的内容