70#优碳钢盘圆的开发.doc

70#优碳钢盘圆的开发    工程硕士学位论文  

摘     要

根据70#优碳钢用户群（拉丝-制弹簧）的使用特点，本文将盘条的拉拔性能作为质量关注点。为获得良好的拉拔性能，要求盘条化学成分稳定，钢质纯净，尽量减少各类非金属夹杂物。金相组织应为细小的珠光体+索氏体+铁素体，其中索氏体占90%以上，脱碳层深度小于产品直径的1.5%。针对这一特点，结合柳钢技术和装备能力,参考国内外高线控轧控冷工艺的成功经验，对70#优碳钢的化学成份、加热温度、加热时间、奥氏体未再结晶区轧制工艺，开轧温度、进精轧温度、吐丝温度、冷却速度等工艺参数进行了研究，选择合理的工艺技术路线，解决关键技术问题和难点问题，开发出了符合用户要求高质量的70#优碳钢。
2010年先后进行2次试验，并对试验结果进行研究分析。试制结果说明，70#的工艺参数设计合理，产品化学成分、力学性能达到标准要求，拉拔性能满足用户要求。
关键词:70#优碳钢，控轧控冷，工艺

Abstract

The drawing property of coil rod was taken as quality focus according to the usage of 70# quality carbon steel. The coil rod must feature with stable chemical composition, pure steel and less non-metal inclusions in order to get good drawing property. The metallurgical structure shall be fine perlite and sorbite which accounted for more than 90% as well as ferrite; the depth of decarburized layer is less than 1.5% of product diameter. Based on these characteristics, the process parameters of 70# quality carbon steel, such as its chemical composition, heating temperature, controlled rolling process in austenite non-recrystallization zone, initial rolling temperature, finishing rolling temperature, laying temperature were researched by combined with the technical and equipment ability in Liugang and referred to the successful experiences of controlled rolling and controlled cooling process of high-speed wire rod at home and abroad to select the reasonable process, solve the key technical problems and develop the high 70# quality carbon steel required by Customers.
Two tests were carried out in 2010 and the testing results were analyzed. The results showed that: process parameter of 70# quality carbon steel was designed reasonably, chemical composition and mechanical property of products reached the standard requirements, and the drawing property met the Customers’ requirements.
Key Words:  70# Quality Carbon Steel; Controlled Rolling and Controlled Cooling; Process

、

目录
摘     要 3
Abstract 4
目录 5
第一章 绪论 6
1.1 70#优碳钢盘圆的特点 6
1.2  70#优碳钢盘圆的应用和市场前景 7
1.3 70#优碳钢盘圆国内外发展与现状 7
1.4  70#优碳钢盘圆质量的主要影响因素 9
1.4.1 化学成分对组织和性能的影响 9
1.4.2 控制轧制与控制冷却对组织和性能的影响 12
1.5 课题意义及研究内容 19
1.5.1课题研究背景及意义 19
1.5.2研究的目的 20
1.5.3主要研究内容与方法 20
1.6 可行性分析 21
1.6.1生产设备 21
1.6.2技术水平 21
第二章  技术要求与主要设备 21
2.1  70#优碳钢盘圆的技术要求 [32] 21
2.1.1化学成分 22
2.1.2产品力学性能 22
2.1.3  高倍组织 23
2.1.4  成品尺寸 23
2.1.5成品表面质量 23
2.1.6  包装 23
2.1.7检验判定 23
2.2 主要生产设备 24
2.2.1冶炼主要设备 24
2.2.2轧制主要设备 25
2.2.3 金相、低倍主要设备 31
2.2.4 力学检验设备 31
第三章 70#优碳钢盘圆工艺设计 32
3.1主要工艺流程 33
3.2采用的关键技术及难点攻关 33
3.2.1冶炼工艺关键技术及难点 33
3.2.2轧制工艺关键技术及难点 36
第四章 70#优碳钢盘圆试制过程及结果 46
4.1试制过程 46
4.1.1第一次试制控冷工艺参数 46
4.1.2第二次试制控轧控冷工艺参数 46
4.2 试制数据 49
4.2.1第1次试制数据 49
4.2.2第二次试制数据 52
4.2.3  70#方坯低倍检验 55
4.2.4  拉拔试验 55
4.2.5 试验方案小结 55
4.2.6  用户使用情况 56
第五章 结 论 56
致   谢 57
参考文献 58