摘要：本文从钢轨不同部位的微观组织出发研究其相应的力学性能，确定钢轨材料各部位微观组织和力学性能的对应关系。实验通过研究钢轨成分来初步描述钢轨的力学特性，并在组织分析中对比进一步表征各部位的力学性能，最后从其力学性能测试试验中对照微观组织来表征其对应关系。通过化学元素分析，脱碳层深度分析可以看出攀钢PD3钢轨具有很高的含碳量，一方面使其强度提高，但是相应的脱碳层深度也处在较高水平，使其表面耐磨性变差。在金相和扫面电镜照片中，可以发现攀钢PD3钢轨大部分组织为片状珠光体结构，少部分有粒状珠光体结构，这为其不同部位提供了不同力学性能。在力学性能测试中，发现攀钢PD3钢轨的抗拉强度和冲击韧性指标较高，这同轨头和轨腰的金相组织中片状和粒状珠光体的分布有关，片状珠光体具有更高的强度，因此广泛分布于轨头部位，而粒状珠光体则能改善轨腰部位的韧性。最后研究片状珠光体的片层间距发现攀钢PD3钢轨片层间距相对较小，这是由于钒钛元素的介入形成碳化物减慢了珠光体的形核速度使其片间距变小，这也是其强度较高的原因之一。

关键词：攀钢PD3钢轨，珠光体，抗拉强度，脱碳层

Abstract：In this paper, the corresponding mechanical properties of different parts of rail are studied, and the corresponding relationship between microstructure and mechanical properties of different parts of rail material is determined. In the experiment, the mechanical properties of the rail were described by studying the rail composition, and the mechanical properties of different parts were further characterized in the microstructure analysis. Finally, the corresponding relationship was characterized by comparing the microstructure with the microstructure in the mechanical property test. After studying the chemical composition and microstructure of PD3 rail of Panzhihua Iron and Steel Co., the mechanical properties of the basic microstructure of the steel for rail can be preliminarily characterized, and the tensile strength and impact toughness of the rail are tested. Some basic mechanical properties require the rail head to be extended in the axial direction for a long time. Therefore, the tensile strength of the rail is higher, while the rail waist is more flexural and its bending performance needs higher strength. Although the chemical composition of the rail parts is roughly the same, its microstructure is not the same and the residual element grade is not the same. This makes the mechanical properties of all parts of the rail meet the requirements of the train running. Through the analysis and study of the microstructure and mechanical properties of the PD3 rail in Panzhihua steel, it is found that the mechanical performance of the rail products is better than other rail products of the same type, which is close to the world's leading level, but in the way of the purification and refinement. There is still room for improvement .

Key words：PD3 rail of Panzhihua Iron and Steel Company，pearlite，tensile strength ,decarburized layer

目录

1.第一章绪论 4

1.1研究目的及意义 4

1.1.1研究目的 4

1.1.2研究意义 4

1.2钢轨介绍 5

1.2.1钢轨基本形状 5

1.2.2钢轨成分及微观组织 5

1.2.3钢轨主要力学性能指标 5

1.3钢轨生产概述 6

1.3.1我国钢轨生产企业概述 6

1.3.2攀钢pd3钢轨 6

1.4钢轨发展现状及展望 7

1.4.1我国钢轨发展现状 7

1.4.2展望 7

2第二章试验方案 9

2.1实验原料 9

2.2主要实验仪器 9

2.3试验方法 9

2.3.1攀钢pd3钢轨金相组织观察 9

2.3.2攀钢pd3钢轨抗拉性能测试 10

2.3.3攀钢pd3钢轨冲击韧性测试 11

3第三章试验数据处理与分析 12

3.1攀钢pd3钢轨成分及微观组织 12