摘要:本论文研究了1500mm宽6mm板厚两个批次BS950钢的边部和心部的原始组织及其硬度,利用X射线衍射精确测定了BS950高强钢边部心部的微结构和马氏体的晶格常数,进行了BS950高强钢板边部和心部的原始组织的扫描电镜观察;测定了升温过程中BS950钢的热膨胀特性和内耗曲线。研究结果表明:BS950钢边部和心部的显微组织是板条状马氏体;硬度实验结果表明钢的平均硬度是42HRC,但是边部比心部的硬度值高,XRD分析发现其点阵常数边部小于心部,半高宽也存在差异,通过对内耗峰的峰高和峰位置进行比对,发现边部的碳析出程度高,通过热膨胀曲线发现钢板边部的热膨胀系数高于心部。这表明BS950钢边部心部存在微观组织上的不均匀性,导致了钢板性能的不均匀。这可能与钢板热轧快冷的冷却方式有关,从而为寻找BS950高强钢起翘的原因提供理论依据。关键词:高强钢;显微组织;内耗峰;热膨胀9120
Original Microstructure and Properties of BS950 High-Strength Steel
Abstruct: The 1500 mm width 6 mm thickness two batches BS950 steel edge and center of the original organization and its hardness were studied in this paper,Accurately determined by X-ray diffraction strength of the BS950 steel edge portion and the central portion of the martensite microstructure lattice constant. The BS950 high-strength steel plate edge and center of the original scanning electron microscopy (sem) observation of the organization. The temperature BS950 steel thermal expansion characteristics and internal friction in the process of the curve were measured. The research results show that the BS950 steel edge and center of the strip martensite microstructure is board and the average hardness of the steel hardness is 42 HRC, but high hardness value than that of the center by batch annealing of edge.XRD analysis found that the lattice constant is less than the core of edge, and a half high width is different. Through to the internal friction peak height and peak position compare, found that carbon precipitation of edge degree is high. Through thermal expansion coefficient of thermal expansion curve found that steel plate edge is higher than the heart. Suggesting BS950 steel edge micro organizational core existence irregularity, led to the uneven steel performance. This may be associated with the cooling system of steel plate hot rolling fast, thus to find the cause of the high strength steel case become warped BS950 provides theory basis.
Key Words: High-strength steel; Microstructure; Friction peak; Thermal expansion
目录
1. 文献综述 1
1.1 低碳低合金高强度钢的国内外发展水平 1
1.2 低碳低合金高强度钢的研究现状与发展趋势 2
1.3低碳低合金高强度钢的基本知识 3
1.3.1低合金高强度钢基本概述 3
1.3.2低合金高强度钢中各元素作用 3
1.3.3低合金高强度钢分类 4
1.3.4低合金高强度宽厚板钢生产工艺 4
1.3.5低合金钢强度钢的发展意义 5
1.4 宝钢3热轧设备介绍 6
1.5 宝钢研究院热轧团队介绍 6
1.6 本课题研究的目的和意义 7
2. BS950高强钢的组织性能研究内容、方法及设备 8
2.1 实验材料及设备 8
2.2 BS950高强钢金相组织实验 9
2.3 BS950钢的硬度实验 9
2.4 扫描电镜试验 10
2.5 X射线衍射试验 11
2.6 内耗试验 11 BS950高强钢原始组织和性能研究+文献综述:http://www.751com.cn/cailiao/lunwen_7728.html