- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Parametric study of laser welding of copper to austenitic stainless steel
摘要： Welding of copper to stainless steel is challenging because of sharp difference in thermophysical properties of materials and the presence of miscibility gap in Fe-Cu system. The parametric study of continuous Yb:YAG laser welding between copper and austenitic stainless steel 316L has been performed. The influence of laser power, welding speed and beam offset from joint line on weld composition, microstructure and tensile properties was studied. The corrosion behaviour of the welds was evaluated in 0.1M NaCl with the potentiostatic pulse testing method, salt fog and immersion tests. In function of copper dilution in the melted zone, different types of microstructure were observed: homogenous solid solution (≥2 at.% Cu), copper-rich net between austenite cells (2-5 at.% Cu) and formation of Cu-rich droplets (> 20 at.% Cu). Selective corrosion of Cu-rich microstructures took place in the melted zone. Tensile properties of the welds were determined by the formation of heat-affected zone in solid copper, where ductile fracture took place.
关键词： stainless steel,copper,corrosion,laser,dissimilar welding
更新于2025-09-12 10:27:22
-
Two pass laser welding of TC4 Titanium alloy to 301L stainless steel via pure V interlayer
摘要： Pulsed laser welding of TC4 Titanium alloy to SUS301 L stainless steel with V sheet as inter-layer was applied. V does not form any intermetallic compound with Ti and Fe. V is used as an interlayer for joining Titanium alloy and stainless steel that the laser successively focused near the Titanium alloy-V and V-stainless steel interfaces. In this way, only two weld zones and unmelted V interlayer can be produced, but also by microstructure of residual solid V interlayer situated between two separately formed weld zones. The unmelted V interlayer acted as a barrier to mixing of the two base materials. The unmelted part of V interlayer also acted as a diffusion barrier between Ti and Fe to avoid the Ti-Fe intermetallics. The tensile strength of joint was 587 MPa accordingly.
关键词： Microstructure,Weld zone,Welding,TC4 Titanium alloy,SUS301L stainless steel,V Interlayer
更新于2025-09-12 10:27:22
-
Wear Tribo-Performances of Laser Cladding Colmonoy-6 and Stellite-6 Micron Layers on Stainless Steel 304 Using Yb:YAG Disk Laser
摘要： Stainless steel material has been widely used in aeronautical, chemical and nuclear industries due to good corrosion resistance. However, the material has less hardness and wear resistance. In this study, two various depositions namely Colmonoy-6 and Stellite-6 have produced on 304 Stainless steel. Besides, the coating was examined to reveal their metallurgical, mechanical and tribological properties. In addition, wear mechanism, wear debris and roughness averages were studied. The outcomes indicate that both coatings show with dendrite structure due to rapid cooling rates. Hardness of the clad surface has improved than substrate material. The results of friction coefficient of specimen with Colmonoy-6 is lower than that of specimens Stellite-6 and substrate. Also, wear resistance of Colmonoy-6 has increased 49 times than substrate sample, which reveals that Colmonoy-6 laser cladding plays role on wear resistance. Adhesive and abrasive are the major wear mechanisms in the present study.
关键词： Wear debris,Microstructure,Stainless steel 304,Roughness,Wear performance,XRD,Laser cladding,Hardness
更新于2025-09-12 10:27:22
-
Computational Investigation of Melt Pool Process Dynamics and Pore Formation in Laser Powder Bed Fusion
摘要： In the laser powder bed fusion additive manufacturing process, the presence of porosity may result in cracks and significantly affects the part performance. A comprehensive understanding of the melt pool process dynamics and porosity evolution can help to improve build quality. In this study, a novel multi-physics computational fluid dynamics (CFD) model has been applied to investigate the fluid dynamics in melt pools and resultant pore defects. To accurately capture the melting and solidification process, major process physics, such as the surface tension, evaporation as well as laser multi-reflection, have been considered in the model. A discrete element method is utilized to model the generation of powder spreading upon build plate by additional numerical simulations. Multiple single track experiments have been performed to obtain the melt pool shape and cross-sectional dimension information. The predicted melt pool dimensions were found to have a reasonable agreement with experimental measurements, e.g., the errors are in the range of 1.3 to 10.6% for melt pool width, while they are between 1.4 and 15.9% for melt depth. Pores are captured by both CFD simulation and x-ray computed tomography measurement for the case with a laser power of 350 W and laser speed of 100 mm/s. The formation of keyholes maybe related to the melt pool front wall angle, and it is found that the front wall angle increases with the increase in laser line energy density. In addition, a larger laser power or smaller scanning speed can help to generate keyhole-induced pores; they also contribute to produce larger sized pores.
关键词： additive manufacturing,melt pool,computational fluid dynamics (CFD),stainless steel,discrete element method (DEM),keyhole
更新于2025-09-12 10:27:22
-
Characterization of Laser-Welded Ti Alloy and Stainless Steel Joint Using Cu Interlayer
摘要： In this study, Cu was used as an interlayer to restrain the formation of brittle Ti-Fe intermetallics when joining Ti alloy to SS. Microstructures of the joint were analyzed using optical microscopy, scanning electron microscopy and x-ray diffraction. Besides, the tensile strength of the joint was also measured. The melting amount of base materials was controlled by changing thickness of Cu interlayer to control the melting proportion in weld. The melting amount of base materials in weld decreased with the thickness of Cu interlayer. The content of Cu solid solution in weld increased with the thickness of Cu interlayer. Ti-Cu compound layer was formed on the Ti alloy side. The width of the Ti-Cu compound layer increased with the increase in heat input. The tensile strength of joint was largely impacted by Ti-Cu compound layer. The tensile strength of joint ?rst increased and then decreased with the increase in width of the Ti-Cu compound layer.
关键词： mechanical property,microstructure,TC4 Ti alloy,laser welding,SUS301L stainless steel
更新于2025-09-12 10:27:22
-
Process Design of Laser Powder Bed Fusion of Stainless Steel Using a Gaussian Process-Based Machine Learning Model
摘要： In this work, a Gaussian process (GP)-based machine learning model is developed to predict the remelted depth of single tracks, as a function of combined laser power and laser scan speed in a laser powder bed fusion process. The GP model is trained by both simulation and experimental data from the literature. The mean absolute prediction error magni?ed by the GP model is only 0.6 lm for a powder bed with layer thickness of 30 lm, suggesting the adequacy of the GP model. Then, the process design maps of two metals, 316L and 17-4 PH stainless steels, are developed using the trained model. The normalized enthalpy criterion of identifying keyhole mode is evaluated for both stainless steels. For 316L, the result suggests that the DH (cid:2) 30 criterion hs should be related to the powder layer thickness. For 17-4 PH, the criterion should be revised to DH hs (cid:2) 25.
关键词： stainless steel,process design,Gaussian process,machine learning,laser powder bed fusion
更新于2025-09-12 10:27:22
-
Fiber laser induced self-organizing structures of 316L stainless steel surface
摘要： When the micro-nano groove structure is processed on the surface of 316L stainless steel by a fiber laser, a self-organizing structure with regular distribution appears. After optimizing the processing parameters, the self-organizing structure with excellent quality can be formed in the groove. In order to further research the properties of the self-organizing structure, the large-area self-organizing structures with different spacings are processed. It is found by the characterization that when the spacing is 50 um, the contact angle of the large-area self-organizing structure is increased by 43.1% with respect to the smooth surface, and its wetting property changes from hydrophilicity to hydrophobicity. The component and the phase composition of the self-organizing structure were found to be consistent with the composition of the original material, and it is preliminarily concluded that the self-organizing structure is formed by the splashing flow of molten liquid in the oxidizing molten pool.
关键词： self-organizing structure,fiber laser,contact angle,component,316L stainless steel
更新于2025-09-12 10:27:22
-
Laser-assisted micro-milling of austenitic stainless steel X5CrNi18-10
摘要： This paper presents a novel Laser-Assisted Micro-Milling (LAMM) process of austenitic stainless steel X5CrNi18-10. The LAMM process is compared with the conventional micro-milling process. Ultra-short pulsed laser radiation is utilized for the structuring of the workpiece surface prior to the micro-milling process. Different laser structures are produced on the workpiece surface at a constant laser scanning speed with various laser powers and laser line spans. The high performance of the developed process is shown by experimental investigations. The effect of laser structuring on the micro-milling forces and temperature indicated the superior performance of the new LAMM process. Cutting forces and temperature could be reduced by up to 70% and 50%, respectively. The results of conventional micro-milling showed that increasing the cutting speed, at a constant undeformed chip thickness, reduced the micro-milling forces. Increasing the cutting speed from 50 to 250 m/min halved both the trust and normal forces, while it slightly improved the surface roughness. On the other hand, increasing the feed per tooth degraded the surface roughness and increased the cutting forces. Furthermore, in conventional milling the workpiece was subjected to high plastic deformation during the cutting process, while side flow, smeared material, metal debris, and cavities were observed on the workpiece surface.
关键词： Laser-assisted micro-milling,Austenitic stainless steel,Ultra-short pulsed laser,Laser structuring,Micro-milling
更新于2025-09-12 10:27:22
-
[Laser Institute of America ICALEO? 2016: 35th International Congress on Applications of Lasers & Electro-Optics - San Diego, California, USA (October 16–20, 2016)] International Congress on Applications of Lasers & Electro-Optics - Controlling the wettability of stainless steel by surface texturing using a high power femtosecond fiber laser
摘要： In this work, stainless steel samples have been textured by a simple and fast one-step laser process. The particularity of this process is the use of an ultrashort pulsed laser technology, combining a high power pulses at high repetition rate. An improved productivity can thus be considered. Successive ablations by IR laser pulses allow to generate dual-scale surface structures. Hierarchical structures, composed of micro-hills on which are superimposed periodic nano-ripples, have been produced at the repetition rate of 50 kHz, by a repeated irradiation of a crossed pattern of parallel lines. In order to increase the process throughput, repetition rates of 100, 250 and 500 kHz have been tested. After an adaptation of the process parameters, topographies with the same dimensions of structures have been created. The presence of these structures modifies the wetting properties of the material. Immediately after laser irradiation the surface becomes hydrophilic; however this wetting state evolves to become superhydrophobic with contact angles higher than 160° and water droplets unable to adhere to the surface. The temporal evolution of the wettability results from the combination of the surface roughness and the chemical composition of this surface. The modeling of the wetting behavior of water droplet, deposited on grooves structures, shows the enhancement of the initial wettability of the surface.
关键词： wettability,superhydrophobic,femtosecond laser,stainless steel,surface texturing
更新于2025-09-12 10:27:22
-
Parametric Study of Underwater Laser Welding on 304 Austenite Stainless Steel
摘要： The underwater laser welding assisted by a single-layer gas torch was carried out on the austenite stainless steel based on the underwater laser welding experimental platform. Butt welding experiments under shallow water were performed to investigate the effects of laser power, welding speed and defocusing distance on the underwater laser welding quality and optimized the process parameters. It was found that the ideal underwater laser weld can be obtained with the laser power of 2.0 kW, the welding speed of 2.0 m/min and the defocusing distance of 1 mm, demonstrating the self-developed single-layer gas-assisted drainage device could create working environment similar to onshore laser welding, by analyzing the metallographic structure and mechanical properties of underwater laser weld and in-air laser weld.
关键词： austenite stainless steel.,Underwater welding,laser welding
更新于2025-09-11 14:15:04