摘要:本文以研究测量轴承钢在不同热处理工艺下体积变化为目标,采用本文提出的测量金属材料相变的新方法——比容差法。运用该方法来测量不同热处理工艺下材料的比容变化,从而分析相变情况。结合X衍射法,定量计算出残余奥氏体和马氏体含量,并对比容差法的数据进行深入分析,深冷后马氏体含量增加,比容相对增大。最后采用螺旋测微仪,测量不同热处理下试样的尺寸变化情况,将数据代入关系式与比容差法数据进行校验,再次验证比容差法对测量金属相变的可行性。本文共对三种轴承钢进行相关实验,最终实验结果表明,比容差法得到结果深冷后试样比容增加;XRD测出峰值计算得到马氏体含量增加;尺寸测量法得到体积增大。综合三组实验表明不同热处理条件下处理的试样, XRD实验和比容差法所得的实验结果吻合。尺寸测量实验验证了比容差法在研究相变时的有效性。57357
毕业论文关键词:轴承钢;比容差法;残余奥氏体;X衍射法
Measurement of the volume change of bearing steel under different heat treatment processes
Abstract: The objective of this paper is to study the volume change of bearing steel under different heat treatment processes. In this paper, a new method for measuring the phase transformation of metal materials is proposed—— specific volume method. Using this method to measure the volume change under different heat treatment processes of materials, so as to analyze the phase transformation. Combined with X-ray diffraction method is quantitatively calculated residual austenite and martensitic content, and specific volume method of data carries on the thorough analysis, cryogenic martensitic content increased, specific volume is relatively large. Finally, the spiral micrometer and measurement of different heat treatment sample size variation, the data substitution relation and second weighing data check again verify specific volume method to measure the metal phase transition feasibility. In this paper, three kinds of bearing steel related experiments. At last, the experiment results show that specific volume method to get the cryogenic sample volume increased; XRD measured peak calculated martensitic content increased; size measurement volume increases. Comprehensive three groups of experiments shows that the different heat treatment conditions of specimen, the
results of XRD experiments and measurement experiment shows changes in its internal organization and two weighing method. The results of the experiment results agree, prove specific volume method in the phase transition of the effectiveness.
Key words: Bearing steel; specific volume method; Retained austenite; X diffraction method;
目 录
1 绪论 1
1.1 选题背景 1
1.1.1 轴承钢简介 1
1.1.2 轴承钢的技术标准 2
1.1.3 轴承钢的性能要求 3
1.2 高碳钢的热处理技术 4
1.2.1 退火 4
1.2.2 淬火与回火 4
1.2.3 深冷 5
1.3选题的目的和意义 6
1.4课题的研究内容 6
2 实验部分 7
2.1 实验材料及热处理工艺 7
2.1.1 实验材料 7
2.1.2 热处理方式 8
2.2 比容差法实验