Investigation on keyhole mode fiber laser welding of SS 316 in a self-protected atmosphere

This work focuses on examining the influence of welding parameters under different welding atmospheres and evaluation of keyhole profile during fiber laser welding operation. The experiments are carried out in two different welding atmospheres, namely self-protected atmosphere of Ar gas and open atmospheric conditions. The effect of these two atmospheric conditions on weld profile formation and dimensions, and microstructural evolution for SS 316 plates are examined. In addition, the keyhole profile is evaluated by using a semi-analytical mathematical model, a point-by-point energy balance determination at the keyhole wall, which is mapped with experimentally measured weld macrographs for similar welding conditions. It has been determined that the weld quality is profound in the case of a self-protected atmosphere with respect to aspect ratio, weld defects, and microstructural characterization. Moreover, better weld bead profile and cleaner weld seam on the upper surface is determined in samples welded in a self-protected atmosphere.

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The effect of laser and welding parameters on keyhole and melt pool behavior during fiber laser welding

International Congress on Applications of Lasers & Electro-Optics ◽

10.2351/1.5061097 ◽

2007 ◽

Cited By ~ 5

Author(s):

Antti Salminen ◽

Anna Fellman

Keyword(s):

Laser Welding ◽

Fiber Laser ◽

Welding Parameters ◽

Fiber Laser Welding ◽

Melt Pool

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Influence of Welding Parameters on weld Depth and Porosity in High Power Fiber Laser Welding

Chinese Journal of Lasers ◽

10.3788/cjl201340.1103004 ◽

2013 ◽

Vol 40 (11) ◽

pp. 1103004

Author(s):

赵琳 Zhao Lin ◽

塚本进 Tsukamoto Susumu ◽

荒金吾郎 Arakane Goro ◽

张岩 Zhang Yan ◽

田志凌 Tian Zhiling

Keyword(s):

Laser Welding ◽

Fiber Laser ◽

High Power ◽

Welding Parameters ◽

Fiber Laser Welding ◽

Weld Depth

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Research on Heat Source Model and Weld Profile for Fiber Laser Welding of A304 Stainless Steel Thin Sheet

Advances in Materials Science and Engineering ◽

10.1155/2018/5895027 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Peizhi Li ◽

Yu Fan ◽

Chonghao Zhang ◽

Zhiyuan Zhu ◽

Wenteng Tian ◽

...

Keyword(s):

Heat Source ◽

Laser Welding ◽

Fiber Laser ◽

Source Model ◽

Depth Of Penetration ◽

Fiber Laser Welding ◽

Heat Source Model ◽

Bead Width ◽

Weld Profile ◽

Simulation Results

A heat source model is the key issue for laser welding simulation. The Gaussian heat source model is not suitable to match the actual laser weld profile accurately. Furthermore, fiber lasers are widely recognized to result in good-quality laser beam output, a narrower weld zone, less distortion, and high process efficiency, compared with other types of lasers (such as CO2, Nd : YAG, and diode lasers). At present, there are few heat source models for fiber laser welding. Most of researchers evaluate the weld profile only by the bead width and depth of penetration, which is not suitable for the laser keyhole welding nail-like profile. This paper reports an experimental study and FEA simulation of fiber laser butt welding on 1 mm thick A304 stainless steel. A new heat source model (cylindrical and cylindrical) is established to match the actual weld profile using Marc and Fortran software. Four bead geometry parameters (penetration depth, bead width, waist width, and depth of the waist) are used to compare between the experimental and simulation results. The results show that the heat source model of cylindrical and cylindrical can match the actual shape of the fiber laser welding feasibly. The error range of the penetration depth, bead width, waist width, and depth of the waist between experimental and simulation results is about 4.1 ± 1.6%, 2.9 ± 2.0%, 13.6 ± 7.4/%, and 18.3 ± 8.0%, respectively. In addition, it is found that the depth of penetration is more sensitive to laser power rather than bead width, waist width, and depth of the waist. Welding speed has a similar influence on the depth of penetration, weld width, waist width, and depth of the waist.

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Optimization of fiber laser welding parameters for high strength aluminium alloy AA7075-T6

Materials Today Proceedings ◽

10.1016/j.matpr.2021.08.276 ◽

2021 ◽

Author(s):

P.S. Dhanaraj ◽

C. Rathinasuriyan

Keyword(s):

Laser Welding ◽

Fiber Laser ◽

Aluminium Alloy ◽

High Strength ◽

Welding Parameters ◽

Fiber Laser Welding

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Numerical And Experimental Analysis of Temperature Distribution And Melt Flow In Fiber Laser Welding of Inconel 625

10.21203/rs.3.rs-982749/v1 ◽

2021 ◽

Author(s):

Iskander Tlili ◽

Dumitru Baleanu ◽

S. Mohammad Sajadi ◽

Ferial Ghaemi

Keyword(s):

Temperature Distribution ◽

Laser Welding ◽

Fiber Laser ◽

Experimental Results ◽

Coarse Grained ◽

Inconel 625 ◽

Welding Parameters ◽

Melt Flow ◽

Fiber Laser Welding ◽

Speed Accuracy

Abstract In these days, laser is a useful and valuable tool. Low input heat, speed, accuracy, and high controllability of laser welding have led to widespread use in various industries. Nickel-based superalloys are creep-resistant materials used in high-temperature conditions. Also, these alloys have high strength, fatigue, and suitable corrosion resistance. Inconel 625 is a material that is strengthened by a complex deposition mechanism. Therefore, the parameters related to laser welding affect the microstructure and mechanical properties. Therefore, in this study, the effect of fiber laser welding parameters on temperature distribution, weld bead dimensions, melt flow velocity, and microstructure was investigated by finite volume and experimental methods. In order to detect the temperature history during continuous laser welding, two thermocouples were considered at a distance of 2 mm from the welding line. The heat energy from the laser beam was modeled as surface and volumetric heat flux. The results of numerical simulation showed that Marangoni stress and buoyancy force are the most important factors in the formation of the flow of liquid metal. Enhancing the laser power to 400 W led to the expansion of the width of the molten pool by 1.44 mm, which was in good agreement with the experimental results. Experimental results also showed that increasing the temperature from 500 °C around the molten pond leads to the formation of a coarse-grained austenitic structure.

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