摘要大多数金属部件在应用中都会受到不同程度的表面损伤，激光熔敷技术就是通过激光技术，融化金属粉末，从而使金属熔敷在使用部件的表面，从而改变使用部件的表面性能。本文通过激光技术，将stellite21粉末熔敷在碳钢板上，熔敷时使用不同的工艺参数，观察熔敷层的宏观形貌，并研究熔敷层的显微组织、硬度、抗摩擦磨损以及耐腐蚀性。实验发现激光功率为1600W，扫描速度增加，熔敷层宽度逐渐减小，熔敷层高度也逐渐减小，熔敷层深度也逐渐减小；扫描速度为8mm/s，激光功率增大，熔敷层宽度逐渐增大，熔敷层高度变化不大，熔敷层深度逐渐增大。硬度测试发现熔敷层的硬度会随着扫描速度增大而增大，随着激光功率的增大而减小。并且进入热影响区时，硬度会突然增大，然后慢慢降低，直到到达基体时，趋于稳定。摩擦磨损实验发现，激光熔敷能够得到一个致密的熔敷层，熔敷层的耐磨性要比基体好很多。腐蚀性实验发现熔敷层的腐蚀性要比基体好得多，而且电压增大，熔敷层会出现点蚀现象。87002

毕业论文关键字：激光熔敷；熔敷层；激光功率；扫描速度；性能测试与分析

Abstract Most metal parts in the application will be subject to varying degrees of surface damage,laser cladding technology is through laser technology,melted metal powder,so that the metal cladding on the surface of parts,to change the surface properties of the component。In this paper, with means of laser technology，Stellite21 powder deposited on carbon steel plate,different process parameters are used in the deposition process,observe the macroscopic morphology of the deposited layer ,the microstructure, hardness, friction and wear resistance and corrosion resistance of the cladding layer were studied。The experimental results show that the laser power is 1600W,with scanning speed increases,the width of cladding layer decreases gradually,deposited layer height is also gradually reduced,penetration depth is also gradually reduced。Scanning speed is 8mm/s，with laser power increase,the width of cladding layer increases gradually,deposited layer height change is not,the penetration depth increases gradually。The hardness test shows that the hardness of cladding layer increases with the increase of scanning speed,with the increase of laser power, the hardness is decreased。 And into the heat affected zone, hardness will suddenly increase, then slowly lower, until the substrate is reached, tends to be stable。 Friction and wear experiments have found that the laser cladding can get a dense layer, the wear resistance of the cladding layer is much better than that of the substrate。 Corrosion tests show that the corrosion resistance of the cladding layer is much better than that of the substrate, And with the voltage increases, there is pitting corrosion in the cladding layer。

Keywords：Laser cladding; cladding layer; laser power; scanning speed；performance test and analysis

目  录

第一章 绪  论 1

1。1引言 1

1。1。1激光熔敷技术简介 2

1。1。2激光熔敷的机理 2

1。1。3激光熔敷的特点 3

1。1。4激光熔敷层材料添加方法简介 4

1。2激光熔敷技术的国内外研究现状 5

1。2。1激光熔敷技术的研究现状 5

1。2。2 我国激光熔敷技术发展存在问题 6

1。2。3激光熔敷技术的应用前景 7

1。3本文主要研究内容与意义