低碳钢液相感应碳氮渗介质的研究
关键词 感应加热 渗碳氮 甲酰胺 反应尾气
毕业设计说明书（毕业论文）外文摘要
Title A Study on the Liquid Media in Liquid Induction Thermochemical Process of Low Carbon Steel
Abstract
Liquid Induction Thermochemical Process is a kind of new method combining Induction Treatment and Thermo-chemical Treatment together. In this thesis, 20CrMnTi is chosen as the original material and treated in the formamide solution for 5 minutes while the temperature is controlled between 830℃ and 930℃. Then the processing temperature is controlled as the const and the processing time ranges from 1 min to 15min to study on the effect of the time on the layer. The hardness of the layers are tested and the metallograhic organizations are observed. The waste gas is collected to be tested on the composition.
The result shows that the layer can be generated to above 100μm in 5 min during 830℃ and 930℃ and carbonitrided layers can be observed as the temperature increases. At 830℃, the nitrided layer becomes thicker as the treating time increases and the carbonitrided layer becomes more clear. The waste gas is proved to be a mix of NH3 and CO.
Keywords Induction heating Thermo-chemical treatment formamide
目 次
1 绪论1
2 实验内容和实验方法 6
2.1 实验材料及准备 6
2.2 实验设备及流程 6
2.3 实验分析方法 7
3 低碳钢感应加热共渗及其介质的研究 9
3.1 20CrMnTi感应加热碳氮共渗的研究9
3.2 共渗过程中气体产物成分研究12
结论 15
致谢 16
参考文献17
1 绪论
热处理技术的发展贯穿着整个人类文明的发展过程。从青铜时代的铜合金铸造冶炼到如今越来越多的加工方法被用于合金的热处理，人类历史伴随着金属热处理的发展进程。随着化学热处理及感应加热技术的发展，金属热处理的技术也向前迈进了一大步。
1．1 钢的渗碳氮热处理工艺
钢的化学热处理是把工件（零件、工模具等）放在一定的活性介质中加热，使活性物质的原子（金属或非金属）渗入工件表层中，改变其表层化学成分的热处理工艺[1]。由于不同工作情况对于工件的性能要求不一样，对加工工艺的要求也不尽相同。如齿轮类零件，要求表面有较高强度而心部有较高的韧性来传递大的扭矩，这种情况下采用化学热处理即可得到表面与心部成分不同的工件。经化学热处理得到工件的组织、性能变化是由表面到心部的渐变，渗层与基体结合牢固，保证工件的质量与使用寿命。