Influence Of Laser Welding Parameters Research Articles

Effect of welding parameters on weld surface roughness, hardness, and microstructure in laser-welded 340BH-steel and pure vanadium

This study delves into the influence of laser welding parameters on the microstructural evolution, surface roughness, and hardness of dissimilar lap joints formed by welding 340BH steel (upper) to cold-rolled pure vanadium (bottom) in an attempt to successfully develop metal membranes by adopting a novel technological route. Specifically, we examined power levels of 0.3 kW and 0.4 kW combined with varying welding speeds (40 mm/s, 50 mm/s, and 60 mm/s). The results indicate that defect-free joints were achievable at the higher welding speed of 60 mm/s. This conclusion is supported by the observed surface roughness profile. Elemental interdiffusion and temperature play pivotal roles in the formation of these dissimilar joints. These factors determine the dimensions of the heat-affected zone (HAZ) and the fusion zone (FZ) under all welding conditions. Notably, the high cooling rates during laser welding hindered the formation of intermetallic phases both in the FZ and at the interface between the metals. Microstructural examination of the HAZ/FZ on the Fe side showed a coarser microstructure when using a power of 0.4 kW, in contrast to the lath martensite observed at 0.3 kW. These observations align with the cooling curve derived from finite element analysis (FEA). FEA was also used to estimate temperature profiles throughout the welded area, and the results were consistent with experimental data. Further microstructural analysis using electron backscattered diffraction (EBSD) revealed a significant phenomenon: the formation of recrystallized grains of vanadium in the HAZ near the FZ on the vanadium side. Microhardness tests, conducted to gauge joint quality, displayed varying hardness levels across the base metal (BM), HAZ, and FZ interfaces. At a power of 0.3 kW, the HAZ displayed greater hardness than the FZ and BM due to the formation of lath martensite. Conversely, at a power setting of 0.4 kW, a reduction in hardness was observed within the HAZ, attributable to coarser ferrite formation.

Determination of the Influence of Laser Welding Parameters on the Weld Quality Assurance of Heat-Resistant Alloys

Abstract: In this study, the method of determining the influence of laser welding parameters on the quality provisions of welded joints made with multicomponent heat-resistant alloys was developed. The regularities of the formation of the welded joint structure of multicomponent heat-resistant alloys obtained by laser welding have been studied. The causes and methodological approaches to eliminate defects in the form of hot cracks were identified. Keywords: laser welding, multicomponent alloys, heat-resistant alloys, welded joints, quality

Analysis of Autogenous Laser Welding in Low Carbon and Large Thickness Steel

With the use of laser welding, it is possible to join different steel, with different thicknesses, with or without the action of protective layers. The quality of laser radiation makes it possible to get certain characteristics that are impossible to get by other processes, such as high welding speeds, less metallurgical effects suffered by the heat-affected zone (ZAC), and this process also does not require filler metal, therefore it is free from possible contamination. Combined with traditional welding methods, laser welding produces narrower weld beads, allowing for better prevention of corrosion and thermal distortions. Although the process already has high industrial knowledge, some random defects, such as porosities and inconsistencies, are still found. This work presents a systematic study to determine the influence of laser welding parameters and how these parameters influence welding defects. For this, the experimental part was carried out in the welding laboratory - LABSOLDA, of the Federal University of Santa Catarina - UFSC, during the laser welding processes, a welding speed of 2.4 m/min was reached. For this experiment, argon was used as a shielding gas and 1020 steel was used as the base material.

Research of Laser Beam Welding of Inconel Alloy

Study of weld joints of nonferrous, Inconel 625 alloy sheets using a new generation disk laser as the green welding technology for the effective manufacturing were carried out, and the results are presented in this paper. Weld joints of the Inconel 625 alloy sheets 2,0 mm thick were welded by laser without an additional material at a flat position, using a high purity argon as the shielding gas. The influence of laser welding parameters on weld quality and mechanical properties of test joints was studied. The influence of welding speed and laser power to the joint quality was investigated. The study of quality and mechanical properties of the joints were determined by metallographic evaluation, tensile and hardness tests.

Influence of Parameters of Laser Beam Welding on Structure of 2205 Duplex Stainless Steel

Abstract Laser welding is used in modern industry, having many advantages comparing to traditional welding technologies. Nowadays, industry sectors such as shipbuilding, automotive and aviation can’t be imagined without laser processing technologies. Possibility of increase of welded joint properties, autogenous welding and high level of process automation makes the technology of laser welding perspective part of the industry. Physical multidimensional processes complexity requires a deeper understanding of the impact of laser welding parameters on the quality of welded joints for industrial implementation. The paper presents results of microstructure investigations of laser beam welded stainless steel under various welding parameters. Welded joints was achieved by Ytterbium fiber laser type without the use of the filler material. Material for test was 2205 ferritic-austenitic duplex stainless steel (DSS) plates with thickness of 8 mm in delivery condition. The objectives of this research was to investigate influence of laser welding parameters on weld geometry of butt-welded joints. Investigations of bead shape revealed correlation between laser beam focus position and weld penetration depth.

Laser Welding of New Grade of Advanced High Strength Steel STRENX 1100 MC

AbstractThe article presents results of investigations on autogenous laser welding of new grade STRENX 1100 MC steel. The modern Disk laser was applied for of 5.0 mm thick butt joints welding. The influence of laser welding parameters, mainly the energy input of laser welding on the penetration shape, weld quality, structure and mechanical performance was investigated. It was found that the investigated steel has surprisingly low carbon equivalent CET just 0.328, and also relatively high temperature of martensitic transformation Msat 430.6°C. Despite very rapid cooling times t8/5in a range from 0.6 to 1.3 s, thus rapid solidification there was no tendency to cracking of weld metal or HAZ. Significant drop of microhardness in the HAZ resulted in a decrease of tensile strength of joints, compared to the base metal. Impact toughness of test joints was at only 50÷60% of the base metal.

Design of Laser Welding Parameters for Joining Ti Grade 2 and AW 5754 Aluminium Alloys Using Numerical Simulation

Joining of dissimilar Al-Ti alloys is very interesting from the point of view of weight reduction of components and structures in automotive or aerospace industries. In the dependence on cooling rate and chemical composition, rapid solidification of Al-Ti alloys during laser welding can lead to the formation of metastable phases and brittle intermetallic compounds that generally reduce the quality of produced weld joints. The paper deals with design and testing of welding parameters for preparation of weld joints of two sheets with different thicknesses from titanium Grade 2 and AW 5754 aluminium alloy. Temperature fields developed during the formation of Al-Ti butt joints were investigated by numerical simulation in ANSYS software. The influence of laser welding parameters including the laser power and laser beam offset on the temperature distribution and weld joint formation was studied. The results of numerical simulation were verified by experimental temperature measurement during laser beam welding applying the TruDisk 4002 disk laser. The microstructure of produced weld joints was assessed by light microscopy and scanning electron microscopy. EDX analysis was applied to determine the change in chemical composition across weld joints. Mechanical properties of weld joints were evaluated using tensile tests and Vickers microhardness measurements.

Optimization for Laser Welding Fillet Joint Based on Response Surface Method

The wide use of galvanized steel in automobile manufacturing brings much challenge to the roof to body-side laser welding process. Fillet joint is an effective way to solve this problem such as pore in laser welding process. However, there is little research on this type of complicated joint process. Focused on this problem, take metallographic size of weld seam as the weld quality criteria, response surface methodology (RSM) is used to study the influence of laser welding parameters on weld seam quality. Finally, the optimum welding parameters are concluded to give technical instructions for the plant production.

Mathematical modelling and optimisation of laser welding of butt joints

Laser welding is characterised by its high power density and concentrated heat input. The weld bead profile of laser welding depends on various parameters and these parameters are to be selected correctly to obtain the desired output. As the trial and error method for selecting weld parameters is very costly, suitable analytical methods has to be established for selecting optimum parameters for welding. In this paper the influence of laser welding parameters on the weld bead profile of butt joints are analysed and discussed. The experimentation is performed based on Box-Behnken design. Mathematical modelling is done to predict the responses and the adequacy of the model is tested using the analysis of variance. Numerical and graphical optimisation techniques are used to find the optimum process range which will improve the weld quality.