摘要GCr15钢作为轴承钢的一种，综合性能较好，使用的范围比较广泛，它的性能与热处理中的预处理及终处理有着不可分割的联系。

本文对GCr15钢进行不同工艺热处理，并采用蔡司显微镜对其进行组织分析、利用XRD对淬火后马氏体与残余奥氏体含量进行分析并进行硬度测试。实验结果表明：GCr15钢经750℃、780℃、810℃及840℃球化退火保温2h分析其球化效果，780℃时碳化物颗粒平均直径较小且弥散分布均匀，碳化物颗粒更加圆整，球化效果最好；然后对其分别加热至820℃、850℃、880℃保温30min油淬+200℃回火2h，850℃淬火温度下的试样针状马氏体明显，碳化物颗粒较小，且黑白区分布较为均匀，残余奥氏体较少，硬度最高；另外对GCr15钢进行1000℃固溶处理，随后分别进行700℃、720℃、740℃高温回火1h、2h、3h，发现720℃高温回火2h时碳化物分布均匀且更加圆整，效果最好；随后对其进行850℃油淬处理后发现碳化物颗粒直径相比较于780℃球化处理+850℃油淬2h试样中更小、更加圆整，残余奥氏体减少，硬度提高；因此确定最佳热处理工艺参数：固溶-高温回火（720℃回火2h）+850℃油淬保温30min+200℃回火2h。87185

毕业论文关键词：GCr15钢；热处理；球化处理；固溶处理

Abstract As one kind of bearing steel, GCr15 steel has better comprehensive performance, wider range of use, its performance and heat treatment in the pretreatment and final treatment has an integral link。

In this paper, the heat treatment of GCr15 steel was carried out, and the microstructure of the steel was analyzed by means of the microscope, and the content of martensite and retained austenite was analyzed and tested by using XRD。 The experimental results show that GCr15 steel with 750 ℃, 780 ℃, 810 ℃ and 840 ℃ spheroidizing annealing insulation 2h analysis the spheroidization effect, 780 degrees is smaller and the average diameter of carbide particles dispersed evenly, carbide particles more rounded, the best ball effect; then the were heated to 820 C and 850 ℃ 30min, 880 ℃ +200 C 2H oil quenching tempering, sample acicular martensite quenching temperature under 850 ℃, carbide particles smaller, and the black and white area distribution is more uniform, less residual austenite, the highest hardness; in addition to 1000 ℃ for GCr15 steel solution treatment, then 700 ℃, 720 ℃ and 740 ℃ 1h, 2h, 3h high temperature tempering, the best found 720 degrees high temperature tempering 2h carbide uniformly and more rounded, effect; carbide particle diameter compared to 780 degrees Celsius to 850 degrees then found oil quenching treatment on the post Spheroidizing + 850 ℃ oil quenching 2H specimen in smaller, more rounded, reduce retained austenite, hardness increased, so to identify the optimum heat treatment process parameters: solid solution and high temperature tempering (720 ℃ tempering 2h) + 850 ℃ oil quenching heat preservation 30min+200 ℃ tempering 2h。

Key words: GCr15 steel; heat treatment; spherical treatment; solid solution treatment

目录

第一章 绪论 1

1。1 国内外轴承钢发展现状 1

1。1。1 国内轴承钢发展现状 1

1。1。2 国外轴承钢发展现状 5

1。2 轴承钢的使用性能 6

1。3 轴承钢所面临的失效情况 7

1。4 一般热处理工艺 7

1。5 本课题主要研究内容 8

第二章 实验材料、设备及方法 9

2。1 实验材料