摘要本文主要进行了 72A 盘条夹杂物数量统计、夹杂物评级以及金相组织评级。 因为夹杂物的数量、大小、类型以及索氏体化率对其质量与性能有着重要的影响。 本文对 A、B、C、D 四个试样（A、B 是同一厂家生产的试样）进行夹杂物的数 量统计、夹杂物的评级以及金相组织的评级。81727

本课题采用的研究方法是：将四个试样进行纵切，然后磨光和抛光。在 100倍光学显微镜下统计 100 个视场中夹杂物的数量和评级。将试样横切进行金相组 织的观察，主要包括索氏体化率、中心偏析、网状碳化物、总脱碳层厚度等。在 光学显微镜下观察并与标准评级图对比，确定金相组织评级。然后对比各厂 72A 盘条夹杂物的数量、评级和金相组织评级。

通过研究表明：A 试样有 31 个夹杂物，B 试样有 34 个夹杂物，C 试样夹杂 物有 22 个，D 试样夹杂物有 20 个。A、B 试样夹杂物的数量相差三个，A、C 试样夹杂物的数量相差 9 个，A、D 试样夹杂物的数量相差 11 个。四个试样夹 杂物主要是 A 类、B 类、C 类，而 D 类、DS 类夹杂物相对较少。四个索氏体化 率基本达到要求，都在 85％以上。四个试均未观察到中心偏析、网状碳化物、 心部马氏体。

毕业论文关键词：帘线钢；夹杂物；金相组织

Abstract This paper conducted a study on the 72A that counting the number of inclusions, microstructure rating and inclusion rating。 Because the number of inclusions, size, type, and patenting rate has a significant impact on their quality and performance。 In this paper, A, B, C, D four samples (A, B is a sample from the same manufacturer) count the number of inclusions, microstructure rating and inclusion rating。

Methods used in this project are: the four samples were slit, and then ground and polished。 Statistics 100 field of view of the number of inclusions and ratings at 100 optical microscope。 The sample cross-section was observed microstructure, including patenting rate, the central segregation, network carbide, total decarburized layer thickness。 Observed under an optical microscope with a standard rating graph compares determining microstructure rating。 And then compare the number of the plant rod 72A inclusions, microstructure ratings and rating。

According to the research: A sample has 31 inclusions, B sample has 34 inclusions, C sample has 22 inclusions, D sample has20 inclusions。 A, the number  of B sample inclusions difference three, A, C Number of samples inclusions difference 9。 A, the number of D sample inclusions difference 11。 Four samples inclusions primarily are Class A, Class B, Class C, and Class D, relatively few DS-type inclusions。 Four patenting rate basically reached the requirements that are more than 85%。 Four test centers were not observed segregation, network carbide, the center of martensite。

Keywords: tire cord steel; inclusion; metallurgical structure

目 录

第一章 绪论 1

1。1  研究背景 1

1。2  研究现状 2

1。2。1 我国轮胎生产情况 2

1。2。2 国内帘线钢生产现状 2

1。2。3 国外帘线钢研究现状 4

1。2。4 存在的问题 4

1。3  钢帘线的生产 5

1。3。1 钢帘线的生产工艺 5

1。3。2 钢帘线的生产技术 5

1。4  帘线钢盘条的质量要求 6

1。4。1 尺寸精度