Improvement of the Laser Direct Metal Deposition Process in 5-axis Configuration

Boisselier, Didier; Sankaré, Simon; Engel, Thierry

doi:10.1016/j.phpro.2014.08.168

Cited by 47 publications

(9 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However with developments in 5-axis toolpaths, more variations in mesoscale and microscale features can be expected. [45] The additional tooling axes result in less planar layering as they generate more complex build strategies and geometries leading to more complex cooling orientations. [36] Consistent hardness values sampled throughout the material support the previous assumption that a well dispersed carbide distribution along with the dendrite morphology reported is representative of homogeneous properties throughout the blown powder DLD material.…”

Section: Accepted Manuscript 22mentioning

confidence: 99%

Microstructural characterisation of a nickel alloy processed via blown powder direct laser deposition (DLD)

et al. 2017

View full text Add to dashboard Cite

A three dimensional structure of varying wall thickness has been manufactured from an alloy similar to 718 and subjected to metallographic characterisation. The technique is evaluated as a process capable of generating complex geometries. This can be used to add features or as a free form fabrication method. However, in order to allow for comparison to structures developed through more traditional techniques, detailed microstructural characterisation has been undertaken to attempt to understand the potential effect of variation on resultant mechanical properties.Samples were extracted from six locations with different wall thicknesses, intricate features and intersecting ligament geometry. A ʺ linearly arrayed structure within a  matrix was consistent throughout the component. Micro-porosity was restricted to isolated, spherical pores less than 1 m in diameter. Electron back-scatter diffraction and X-ray computed microtomography quantitative microstructural analysis techniques have been utilized to assess the influence of layering upon microporosity, patternation and grain structure.A detailed comparison is also made between blown powder Direct Layer Deposition (DLD) and a similar deposition technique, shaped metal deposition (SMD). Blown powder DLD produces a smaller weld pool and results in a more consistent microstructure than SMD, with less evidence of unfavourable phases brought about by prolonged exposure to high temperatures. The improved microstructure, however,

show abstract

Section: Accepted Manuscript 22mentioning

confidence: 99%

Microstructural characterisation of a nickel alloy processed via blown powder direct laser deposition (DLD)

et al. 2017

View full text Add to dashboard Cite

show abstract

“…For its development, research nowadays involves all kinds of areas, such as process optimization [5][6][7][8][9], modelling/simulation [10][11][12][13][14], and material microstructure and mechanical properties [15][16][17][18][19].…”

Section: Introductionmentioning

confidence: 99%

The Influence of the Powder Stream on High-Deposition-Rate Laser Metal Deposition with Inconel 718

Chen

Pirch

Gasser

et al. 2017

Metals

View full text Add to dashboard Cite

Abstract:For the purpose of improving the productivity of laser metal deposition (LMD), the focus of current research is set on increasing the deposition rate, in order to develop high-deposition-rate LMD (HDR-LMD). The presented work studies the effects of the powder stream on HDR-LMD with Inconel 718. Experiments have been designed and conducted by using different powder feeding nozzles-a three-jet and a coaxial powder feeding nozzle-since the powder stream is mainly determined by the geometry of the powder feeding nozzle. After the deposition trials, metallographic analysis of the samples has been performed. The laser intensity distribution (LID) and the powder stream intensity distribution (PID) have been characterized, based on which the processes have been simulated. Finally, for verifying and correcting the used models for the simulation, the simulated results have been compared with the experimental results. Through the conducted work, suitable boundary conditions for simulating the process with different powder streams has been determined, and the effects of the powder stream on the process have also been determined. For a LMD process with a three-jet nozzle a substantial part of the powder particles that hit the melt pool surface are rebounded; for a LMD process with a coaxial nozzle almost all the particles are caught in the melt pool. This is due to the different particle velocities achieved with the two different nozzles. Moreover, the powder stream affects the heat exchange between the heated particles and the melt pool: a surface boundary condition applies for a powder stream with lower particle velocities, in the experiment provided by a three-jet nozzle, and a volumetric boundary condition applies for a powder stream with higher particle velocities, provided by a coaxial nozzle.

show abstract

“…Boisselier et al [28] found some of the same patterns in reflected laser signals and the track geometry. The signals have the potential to monitor the deposition height.…”

Section: Online Monitoring Of Deposition Height and Widthmentioning

confidence: 72%

Analysis of In Situ Optical Signals during Laser Metal Deposition of Aluminum Alloys

Wang

Huang

2021

Crystals

View full text Add to dashboard Cite

During laser metal deposition (LMD) of thin-walled aluminum alloy structures, the deposition height and width is hard to keep stable because of the special properties of aluminum alloys, such as high reflectivity to laser beams, low viscosity, and high thermal conductivity. Monitoring the LMD process allows for a better comprehension and control of this process. To investigate the characteristics of the aluminum alloy LMD process, three real-time coaxial optical sensors sensitive to visible light, infrared light, and back-reflected lasers ere used to monitor the aluminum alloy LMD process. Thin-walled parts were deposited with different laser power, and the characteristics of the three in situ signals are analyzed. The results show that there exists high linear correlation between reflected laser and accumulated deposition height. A laser reflection model was built to explain the correlation. Besides, the infrared light is linearly correlated with deposition width. Overall, the results of this study show that the optical signals are able to reflect the deposition height and width simultaneously. Infrared light signals and reflected laser signals have the potential to serve as the input of online feedback geometry control systems and real-time defect alarm systems of the LMD process.

show abstract

Improvement of the Laser Direct Metal Deposition Process in 5-axis Configuration

Cited by 47 publications

References 7 publications

Microstructural characterisation of a nickel alloy processed via blown powder direct laser deposition (DLD)

Microstructural characterisation of a nickel alloy processed via blown powder direct laser deposition (DLD)

The Influence of the Powder Stream on High-Deposition-Rate Laser Metal Deposition with Inconel 718

Analysis of In Situ Optical Signals during Laser Metal Deposition of Aluminum Alloys

Contact Info

Product

Resources

About