摘要304不锈钢具有良好的耐蚀性能、加工性能和焊接性能，广泛应用于建材、化学、工业、食品等行业，是需求量最大的不锈钢之一。而针对304不锈钢热处理，书本上仅规定了具体的工艺参数，并没有详细说明热处理后钢的组织结构和力学性能的变化。本文以直径为16mm的304不锈钢棒为研究对象，通过改变固溶温度、固溶时间和冷却方式进行热处理实验研究，采用蔡司显微镜、布氏硬度计来分析不同热处理制度对试样组织和力学性能的影响，以获得304不锈钢较佳的热处理工艺。87111

通过对固溶温度影响的研究，结果表明：随着固溶温度升高，晶粒长大。硬度值降低。在1050-1100℃时，晶粒均匀，大小中等，硬度值下降趋势减缓，碳化物得到了充分固溶。

通过对固溶时间影响的研究，结果表明：固溶时间实验结果跟固溶温度实验相似，但相较于固溶温度实验，晶粒长大不明显，在保温40-60min时硬度值下降趋势减缓。

通过对冷却方式影响的研究，结果表明：冷却方式的变化对试样晶粒大小没有影响。而冷却速度变快，试样内外部出现温差，从而产生的内应力具有强化作用，使得硬度升高。

综合来看，304不锈钢在1050-1100℃下保温40-60min，水冷后有很好的组织和力学性能。

毕业论文关键词：304不锈钢；固溶处理；组织结构；力学性能

Abstract 304 stainless steel has a good corrosion resistance, processing and welding property,it is widely used in building material, chemical, industrial, food and other industries and it is one of the largest demand for stainless steel。Only the specific process parameters are specified about 304 stainless steel in the book。The change of microstructure and mechanical properties of the steel after heat treatment was not explained in detail。So the research object of this paper is 304 stainless steel with 16mm diameter。I will use the microscope and the hardness tester to analyze the influence of different heat treatment on the sample by changing the solid solution temperature, the solid solution time and the cooling-down method。Hoping that through the research can deepen the awareness about this steel。

The results with solid solution temperature show that grain size is growing, and the hardness value is decreasing with the increase of solid solution temperature。When the temperature is about 1050-1100℃,grain size is uniform and downward trend of hardness is retard,The carbide was fully dissolved。

The results with Solid solution time show that the test with solid solution time is similar to the test with solid solution temperature 。But the grain growth is not obvious。downward trend of hardness is retard through the heat preservation of 40-60min。

The results with cooling-down method show that the change of cooling mode had no effect on the grain size。The cooling rate becomes fast, the temperature difference between inside and outside of the sample is produced。 the internal stress has a strengthening effect, and it makes the hardness increased。

Keywords: 304 stainless steel; solid solution treatment; microstructure; mechanical properties

目  录

第一章 绪论 1

1。1 不锈钢生产和现状 1

1。1。1 不锈钢的概述 1

1。1。2 不锈钢的发展 1

1。1。3 不锈钢的生产中存在的问题 2

1。2 不锈钢的概述 2

1。2。1 不锈钢的分类 2

1。2。2 合金元素对不锈钢的影响