20钢液体渗碳工艺及性能研究分析.doc

北华航天工业学院毕业论文 4 - 摘 要 液体渗碳就是钢件在液体渗碳介质中加热保温，使碳原子渗入钢件表面，使其表面的碳浓度发生改变，从而获得具有一定表面含碳量和一定浓度梯度的热处理工艺。当前液体渗碳正着无毒无污染的方向进行，像NaCl无毒液体渗碳剂、603无毒液体渗碳剂及其改进行、QPQ技术等。 本文主要研究了20钢在经过液体渗碳后的组织与性能，并研究了液体渗碳的渗剂、工艺参数，并且与未经过此渗碳的工艺进行了分析对比。液体渗碳剂由基盐、催渗剂、渗碳剂组成，工艺简单，便于实施，是一种可获得渗层性能好的化学热处理方法。 通过渗碳、淬火、回火处理，发现随着加热温度的升高，工件表面硬度和渗层厚度不断增加，随着加热时间的增加，工件表面硬度和渗层厚度也不断增加。 关键词：20钢 液体渗碳 耐磨 硬度 渗碳剂 Abstract Liquid carburizing is carburizing steel parts in a liquid medium，heat insulation，of carbon atoms into the surface of steel,to change the carbon concentration of the surface,to obtain a certain surface concentration gradient of carbon content and heat treatment process must .Liquid carburizing is the current direction of the toxic pollution,NaCl as non-toxic liquid carburizing agents,603non-toxic liquid carburizing agents and their changes were,QPQ technology. This paper studies the liquid after the 20 steel and properties after carburizing，and to study the penetration of liquid carburizing，process parameters and the application process in 20 steel,And with a total penetration of this technology has not been analyzed and compared. Liquid carburizing agent from the base salt,composed of carburizing agent,process is simple,easy to implement，Nitrided layer is a good performance of available chemical treatment methods. By carburizing, quenching and tempering treatment, found that increasing the heating temperature increases, surface hardness and thickness of the increasing infiltration, with the increase of heating time, infiltration surface hardness and thickness are also increasing. Key words: 20 steel liquid carburizing wear hardness carburizing agent 目 录 摘要···································································· Ⅰ Abstract································································ Ⅱ 第1章 绪论···························································· 1 1.1 项目的发展背景·················································· 1 1.2 项目发展趋势和研究意义····································