Numerical model of transient convection pattern and forming mechanism of molten pool in laser cladding

In the high-piled up process of laser cladding rapid forming , the distance between aser molten pool center and flour will increase along with the cladding layer ,which will cause the effect of light powder coupling getting worse, even directly lead to failure. The article proposed characteristics of the double-spot ,formed by molten pool and reflection of laser surface;used VC++ 6.0 as the development platform of image processing to calculate two spot centroid distance by dealing two spot image with the process of gray processing, Gaussian smoothing, binary threshold segmentation, area centroid calculation, the centroid coordinate distance calculation.At the same time , controlling laser head Z to move in accordance with the value increment,to increase the stability of forming process and forming quality.

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The Effect of Thermal Field on the Deposition of Fe-TiC on Carbon Steel Using Laser Cladding

Volume 3: Design and Manufacturing, Parts A and B ◽

10.1115/imece2010-38315 ◽

2010 ◽

Cited By ~ 1

Author(s):

Masoud Alimardani ◽

Ali Emamian ◽

Amir Khajepour ◽

Stephen F. Corbin

Keyword(s):

Carbon Steel ◽

Numerical Model ◽

Laser Cladding ◽

Thermal Field ◽

Deposition Process ◽

Time Dependent ◽

Experimental Investigations ◽

Thermal Fields ◽

Temperature Distributions ◽

Laser Cladding Process

In this paper, a numerical and experimental method is used to investigate the effect of thermal fields on the deposition of Fe-TiC using the laser cladding process. Since in laser cladding temperature distributions and consequent rapid cooling rates determine the microstructure and final physical properties of the deposited layers, a 3D time-dependent numerical model is used to simulate the cladding process parallel to experimental analysis. The numerical results are used to study the temperature distributions and their evolutions throughout the deposition process. The experimental and verified numerical outcomes are then employed to study the variations of the microstructures of the deposited material as well as correlation between the formed microstructures and temperature distributions across the deposition domain. The numerical and experimental investigations are conducted through the deposition of Fe-TiC on the substrate of AISI 1030 carbon steel using a 1.1 kW fiber laser. The experimental results confirm that by increasing the substrate temperature throughout the process the distribution of the TiC particles changes along with the deposited tracks and the TiC particles start forming clusters at the top of the clad.

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Design of Forming Shape Measurement System for Laser Molten Pool in Laser Fabricating

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.37-38.327 ◽

2010 ◽

Vol 37-38 ◽

pp. 327-330 ◽

Cited By ~ 4

Author(s):

Jian Bo Lei ◽

Zhen Wang ◽

Li Feng Liu

Keyword(s):

Laser Cladding ◽

Molten Pool ◽

Detection System ◽

Shape Measurement ◽

Optical Elements ◽

Shape Distribution ◽

Special Software ◽

Measurement Results ◽

Destructive Measurement ◽

Non Destructive

In order to study forming shape distribution of laser molten pool in laser fabricating, a CCD-based image detection system was developed. The system mainly consists of a CCD-based detector, optical elements, an image acquisition card and its special software. Experiments on shape measurement of the laser molten pool were carried out. It was shown that 2D morphology and the dimension of laser molten pool could be measured in real time. The (X, Y) dimension of the laser molten pool in laser cladding was (2.6 mm, 2.5 mm) with an approximately ellipsoidal shape. Laser cladding parameters were optimized according to the measurement results. It was a non-destructive measurement method, which would be a new method for online measurement and feedback control in laser fabricating.

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Hybrid forming mechanism of patternless casting and laser cladding

Frontiers of Mechanical Engineering ◽

10.1007/s11465-019-0550-1 ◽

2019 ◽

Vol 14 (4) ◽

pp. 393-401

Author(s):

Zhongde Shan ◽

Fuzhen Sun ◽

Yang Liu

Keyword(s):

Laser Cladding ◽

Forming Mechanism

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Effects of electromagnetic compound field on the escape behavior of pores in molten pool during laser cladding

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2019.125198 ◽

2020 ◽

Vol 383 ◽

pp. 125198 ◽

Cited By ~ 3

Author(s):

Yong Hu ◽

Liang Wang ◽

Jianhua Yao ◽

Hongchao Xia ◽

Juehui Li ◽

...

Keyword(s):

Laser Cladding ◽

Molten Pool ◽

Escape Behavior

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Study on Laser Cladding Coatings of Ni-Based Alloy/TiC/Nickel-Coated Graphite on Steel Substrate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.450.214 ◽

2010 ◽

Vol 450 ◽

pp. 214-218 ◽

Cited By ~ 2

Author(s):

Li Xia Ying ◽

Li Dong Jiang ◽

Fan Kai Kong ◽

En Xia Yang

Keyword(s):

Wear Resistance ◽

Friction Coefficient ◽

Laser Cladding ◽

Metal Surfaces ◽

Steel Substrate ◽

Extreme Conditions ◽

Cross Sectional ◽

Graphite Composite ◽

Forming Mechanism ◽

Uniform Microstructure

In order to improve the antiwear and antifriction performances of tribological metal surfaces for the extreme conditions, the composite coating has been fabricated on metal surfaces by the technology of laser cladding. In the experiment, Ni-based alloy, TiC and Nickel-coated graphite are used as the main ingredients of composite. The cross-sectional macrographs, microstructure, compositions, microhardness, tribological properties and the forming mechanism of the coating was tested and analyzed. Results show that laser cladding Ni60A/TiC/Nickel-coated graphite composite can obtain excellent coating with fully compact and uniform microstructure, and good interface with the substrate. The microhardness of the clad coating is over HV1000, which is five times higher than that of the steel substrate. The friction coefficient is reduced to about 0.4-0.5 in comparison with that of the steel substrate (about 0.7-0.8). At the same time, the wear resistance of the clad coating is also improved greatly.

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Modeling of temperature distribution and clad geometry of the molten pool during laser cladding of TiAlSi alloys

Optics & Laser Technology ◽

10.1016/j.optlastec.2021.107277 ◽

2021 ◽

Vol 142 ◽

pp. 107277

Author(s):

Chen Shen ◽

Chonggui Li ◽

Yajun Guo ◽

Chuanming Liu ◽

Xuanjun Zhang ◽

...

Keyword(s):

Temperature Distribution ◽

Laser Cladding ◽

Molten Pool

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Numerical Analysis of Particulate Migration Behavior within Molten Pool during TIG-Assisted Droplet Deposition Manufacturing of SiC Particle-Reinforced Aluminum Matrix Composites

Materials ◽

10.3390/ma14092430 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2430

Author(s):

Yubin Zhang ◽

Jun Du ◽

Huafeng Wang ◽

Hua Li ◽

Xiaoyun Zhao

Keyword(s):

Numerical Model ◽

Molten Pool ◽

Aluminum Matrix ◽

Heat Transfer Fluid ◽

Aluminum Matrix Composites ◽

Migration Behavior ◽

Matrix Composites ◽

Droplet Deposition ◽

The Impact ◽

Sic Particle

A transient three-dimensional (3D) numerical model was established to illustrate the heat transfer, fluid flow and particle migration behaviors in the molten pool during TIG-assisted droplet deposition manufacturing (DDM) of SiC particle-reinforced aluminum matrix composites (AMCs). The effect of temperature-dependent physical properties and the interaction between the SiC reinforcement and the liquid metal matrix were considered. A double-ellipsoidal volumetric heat source model was adopted to simulate the energy interactions between the pulse square-wave variable polarity TIG welding arc and the moving substrate. Free surface fluctuations of molten pool due to arc force and sequential droplet impact are calculated with volume of fluid (VOF) method in a fixed Eulerian structured mesh. The numerical model, capable of capturing the impact, simultaneous spread, and phase change of the droplets as well as the motion trajectory and terminate distribution state of the reinforcement particles, is key tool to understand the formation mechanism of the TIG-assisted DDM of SiC particle-reinforced AMCs. The numerical model was validated by the metallographic observations, and the calculated particle distribution and solidification morphology of deposited layer agree well with the experimental measurements.

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