摘要本文对光纤激光焊接304不锈钢的工艺进行了研究，采用光纤激光对6mm304不锈钢进行对接焊接试验，分别从激光功率、焊接速度、离焦量等方面对实验进行优化。分析了焊接接头的外观形貌、微观组织、显微硬度以及抗拉强度等接头性能，从激光焊接304不锈钢的工艺特点、焊缝组织和性能特点等，对304不锈钢材料的焊接性、成形情况进行研究。最终获得了比较合适的焊接工艺，形成了较为优质的高强度焊接接头。实验结果表明，在光纤激光功率4kW，焊接速度0.038m/s，焦点位置在工件表面时，则可获得较为满意的焊接效果。此时焊缝的硬度稍高于母材，但低于热影响区。焊缝的最大抗拉强度为515MPa，达到母材抗拉强度的83%。断裂发生于熔合区靠焊缝侧。
关键词 304不锈钢； 激光焊接； 焊缝； 组织性能
毕业论文设计说明书（论文）外文摘要
Title Study of Fiber Laser Welding for 304 Stainless Steel
Abstract
In this paper the technology of optical fiber laser welding of 304 stainless steel was studied，the optical fiber laser is adopted to 6 mm304 stainless steel butt welding experiment was carried out，respectively from the laser power，welding speed，from the aspects such as coke deposition of experimental optimization. Analyses the appearance of the welding joint morphology，microstructure，microhardness and tensile strength of joint performance，from the technical characteristic of laser welding of 304 stainless steel and weld organization and performance characteristics，the weldability of 304 stainless steel material and forming condition were studied. We eventually won the appropriate welding process，and formed a relatively high quality and high strength of welded joint. The experimental results show that in optical fiber laser power 4 kw，welding speed 0.038 m/s，the focus position on the workpiece surface，if two pieces of plate surface clean，seamless and docking，a satisfactory welding effect can acquire. Weld hardness is slightly higher than the parent metal，but lower than the heat affected zone. The maximum tensile strength of 515 mpa，which is 83% of the parent metal tensile strength.Fracture occurred in the fusion zone depend on weld side .
Keywords 304 stainless steel; fiber laser welding; welding seam; microstructure and properties structure property
目录
1 绪论 1
1.1 选题背景及意义 1
1.2 激光焊的研究发展 1
1.3 研究课题的目标、内容 4
2 试验材料、设备与方法 6
2.1 试验材料 6
2.2 焊接设备 6
2.3 实验方法 8
3 304不锈钢光纤激光焊接头宏观形貌观察 10
3.1 试验工艺参数设计 10
3.2 激光焊焊接接头宏观形貌观察 10
3.3 本章小结 17
4 304不锈钢激光对接焊接接头微观组织与力学性能分析 19
4.1 焊接接头显微组织特征 19
4.2 焊接接头力学性能分析 20
4.3 焊接接头抗拉强度及断口形貌分析 21
4.4 本章小结 24
结 论 25
致 谢 26
参考文献27
1 绪论
1.1 选题背景及意义
激光焊因其具有高效、优质、低污染及焊接变形小等优点，在船舶、航空、汽车等工业及医学上应用广泛[1]。
近年来，高功率光纤激光技术及其产业化的成熟，已经对CO2激光器的市场造成了严重的冲击与挑战。各种高功率光纤激光加工设备已经进入了人们的眼球，光纤激光焊接技术逐渐成为研究的热点。 304不锈钢激光对接焊缝焊接试验研究:http://www.751com.cn/cailiao/lunwen_14233.html