摘要本文研究了40Cr钢高温淬火工艺参数对组织的影响。在高温淬火后，不同的保温时间对马氏体形成后的硬度影响，热处理试样进行金相显微组织进行观察、摄像；分析淬火组织组成及其形态、尺寸大小和分布；测定组织硬度等性能。在 (790－900)℃范围内淬火情况，随着淬火加热温度的升高，40Cr钢的强度、硬度升高。具体选定的正火状态样品直径为12mm，具体工艺参数分别为840℃，880℃，930℃，840℃的保温时间分别为2分钟，5分钟，10分钟，30分钟。880℃的保温时间分别为2分钟，5分钟，10分钟。930℃的保温时间为2分钟，5分钟，10分钟。可得实验结论：在840-930℃范围内淬火时，随着温度升高，40Cr钢的硬度升高；随淬火温度升高，组织中铁素体含量逐步减少，其分布形态也发生明显变化。52611

毕业论文关键字：40Cr;高温淬火;硬度;工艺参数

Abstract

The effect of process parameters on Microstructure of 40Cr steel was studied in this paper. After quenching at high temperature, the influence of different holding time on the hardness of martensite is studied. Microstructure of heat treated samples were observed by metallographic microscope. Analysis of quenching microstructure and its morphology, size and distribution. Determination of tissue hardness and other properties In the range of (790 to 900), the strength and hardness of 40Cr steel increase with the increase of quenching heating temperature.Specific selected normalized sample diameter of 12mm, specific process parameters were 84 DEG C, 880 DEG C, 930 DEG C, 840 C holding time respectively 2 minutes, 5 minutes, 10 minutes, 30 minutes. 880 degrees of heat preservation time is 2 minutes, 5 minutes, 10 minutes.Available experimental conclusion: in the 840-930 temperature range of quenching, with the increase of temperature, hardness of 40Cr steel increases; with the increase of quenching temperature, the organization of ferrite content gradually reduced, the distribution also occur significant changes.

Key words:40Cr; High temperature quenching; hardness;process parameters

目录

1绪论 3

1.1钢的简介 3

1.1.1钢的分类 3

1.1.2钢的普通热处理及性能指标 4

1.2 40Cr钢的介绍 5

1.2.1 40Cr钢 6

1.2.2 40Cr特性及用途 6

1.3 40Cr钢热处理传统工艺概述 6

1.4 热处理现代新工艺 7

1.4.1 控气氛热处理 7

1.4.2 真空热处理 7

1.4.3 形变热处理 7

1.4.4 高温淬火 8

1.5选题的目的和意义 9

1.6研究的内容和目标 9

1.6.1研究内容 9

1.6.2 预期目标 9

2 实验方法 10

2.1 实验材料 10

2.2 实验设备与仪器 10

2.2.1 热处理样品设备 10

2.2.2 热处理样品切割 10

2.2.3 砂轮机机器 11

2.2.4箱氏电阻炉 11

2.2.5 砂纸及抛光机 11