Numerical Study on Laser Cladding of BT20 Alloy

2012 ◽  
Vol 479-481 ◽  
pp. 850-853
Author(s):  
Qing Ming Chang ◽  
Jing Yuan ◽  
Yin Kai Yang ◽  
Xia Chen ◽  
Chang Jun Chen ◽  
...  

A 3-D modeling based on the numerical resolution of fluid flow and heat transfer are utilized to investigate the thermal phenomena during laser laser-cladding processes of BT20 alloy. From this model, it has been found that the shape and size of the molten pool in the work piece are affected by laser cladding parameters such as scanning speed and the incident laser power. The effects of process parameters on the melt pool are quantitatively discussed by numerical analysis. Furthermore, it has been observed that the surface tension temperature coefficient, Marangoni convection, which is sensitive to the active elements in the titanium alloy composition, also affect the pattern of the fluid flow in the molten pool.

2011 ◽  
Vol 80-81 ◽  
pp. 46-50
Author(s):  
Qing Ming Chang ◽  
Chang Jun Chen ◽  
Xia Chen ◽  
Si Qian Bao ◽  
Chen Gang Pan

A 3-D modeling based on the numerical resolution of fluid flow and heat transfer for laser-cladding processes of In718 Superalloy is proposed. The implementation of developed procedures allowed us to treat the problem with specific and complex boundary conditions. The applied loading is a moving heat source that depends on process parameters such as power density, laser beam diameter and scanning speed. The effects of process parameters on the melt pool are quantitatively discussed by numerical analysis. The computational results present good coincidences with the corresponding experiments of laser cladding process.


2011 ◽  
Vol 214 ◽  
pp. 224-229 ◽  
Author(s):  
Qing Ming Chang ◽  
Chang Jun Chen ◽  
Xia Chen ◽  
Si Qian Bao

In this paper, a three-dimensional simulation model for laser-cladding processes of magnesium alloys is proposed. The applied loading is a moving heat source that depends on process parameters such as power density, laser beam diameter and scanning speed. The effects of process parameters on the melt pool are quantitatively discussed by numerical analysis. In these parameters, Marangoni force is the most important in affecting the molten metal flow and the contour of the melt pool. Both the length and depth of the melt pool vary sharply with temperature dependence of surface tension when the absolute value of this temperature dependence is at lower value.


2005 ◽  
Vol 127 (9) ◽  
pp. 978-986 ◽  
Author(s):  
J. Choi ◽  
L. Han ◽  
Y. Hua

Laser aided Directed Material Deposition (DMD) is an additive manufacturing process based on laser cladding. A full understanding of laser cladding is essential in order to achieve a steady state and robust DMD process. A two dimensional mathematical model of laser cladding with droplet injection was developed to understand the influence of fluid flow on the mixing, dilution depth, and deposition dimension, while incorporating melting, solidification, and evaporation phenomena. The fluid flow in the melt pool that is driven by thermal capillary convection and an energy balance at the liquid–vapor and the solid–liquid interface was investigated and the impact of the droplets on the melt pool shape and ripple was also studied. Dynamic motion, development of melt pool and the formation of cladding layer were simulated. The simulated results for average surface roughness were compared with the experimental data and showed a comparable trend.


Author(s):  
M. Jamshidinia ◽  
F. Kong ◽  
R. Kovacevic

A three-dimensional (3D) numerical model is developed by using control volume method to analyze the effects of the electron beam scanning speed on the temperature distribution and fluid flow of the liquid phase in the electron beam melting® (EBM) of Ti-6Al-4V powder. The numerical calculations are performed by Fluent codes, in which thermal analyses with and without considering fluid flow in the molten pool are compared. A series of experiments are performed with an Electron Beam Melting® machine to verify the numerical accuracy. Compared to thermal analysis without considering convection in the molten pool, a closer numerical prediction of geometrical size of molten pool to the experimental data can be achieved by using thermal and fluid flow modeling. The difference between the melt pool geometry in the two models is due to the consideration of the effects of the outward flow in the fluid flow model caused by surface tension.


Applied laser ◽  
2014 ◽  
Vol 34 (5) ◽  
pp. 389-394
Author(s):  
王维 Wang Wei ◽  
刘奇 Liu Qi ◽  
杨光 Yang Guang ◽  
钦兰云 Qin Lanyun ◽  
薛雄 Xue Xiong

Author(s):  
S Kumar ◽  
S Roy

A two-dimensional model has been developed to predict the temperature field and melt pool shape during blown powder laser cladding. A finite volume method has been used to solve the two-dimensional energy equation for a body moving relative to a stationary laser heat source. A boundary fitted coordinate system has been employed as the built-up surface geometry is complex. Important dimensionless groups representing laser parameters power ( P) and scanning speed ( U) and the process parameters built-up height and average dilution are identified. The effect of laser parameters on process parameters is investigated. For cladding P/U should always be kept low (less than 1) to reduce the average dilution, and in order to achieve the desired clad height the power level P should be controlled.


Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 203
Author(s):  
Fangping Yao ◽  
Lijin Fang

In order to improve the work efficiency and save resources in the process of laser cladding on the H13 steel surface, based on COMSOL, by combining computer simulation and experiment, a plane continuous heat source model was used to simulate and analyze the temperature and stress field. The optimal power and scanning speed were obtained. It is found in the simulation process that the thermal sampling points stress increases with the increase of laser power and scanning speed. Because of the existence of solid–liquid phase variation in the laser cladding process, there are two peaks in the maximum thermal stress cycle curve of the sample points located in the molten pool, and the starting and ending time of each sample point’s peak value is basically the same. When the sample point is outside the molten pool, because the metal at the corresponding location is not melted, so there is no obvious peak value in the thermal stress cycle curve. With the increase of cladding layer depth corresponding to each sample point, the variation range of the two alternating thermal stress peaks increases first and then decreases, while the duration increases. According to the peak value of alternating thermal stress at the sampling point, the molten pool depth can be predicted. The residual stress analysis of the cladding layer is carried out according to the analysis results of temperature field and stress field. Through the actual cladding experiment, it is found that the depth of molten pool in the simulation results is basically consistent with the experimental results. All simulation results are verified through actual cladding experiments.


Applied laser ◽  
2014 ◽  
Vol 34 (5) ◽  
pp. 389-394
Author(s):  
王维 Wang Wei ◽  
刘奇 Liu Qi ◽  
杨光 Yang Guang ◽  
钦兰云 Qin Lanyun ◽  
薛雄 Xue Xiong

2012 ◽  
Vol 538-541 ◽  
pp. 1874-1877 ◽  
Author(s):  
Shuai Zhang ◽  
Yan Ling Tian ◽  
Fu Jun Wang

A 3-dimensional (3D) thermal distribution computational methodology for laser cladding is presented. Based on the developed model, which considers the latent heat and change of conductivity in different phase, the transient temperature fields for the preplaced laser cladding processing are performed. The effect of processing parameters including laser power, scanning speed and laser spot diameter on melt pool temperature filed was extensively discussed and some conclusions were drawn.


Author(s):  
L. Han ◽  
J. Choi

Directed Metal/Material Deposition (DMD) process is one of additive manufacturing processes based on laser cladding process. A full understanding of laser cladding process is a must to make the DMD process consistent and robust. A two dimensional mathematical model of laser cladding was developed to understand the influence of fluid flow to the mixing, dilution, and deposition dimension, incorporating melting, solidification, and evaporation phenomena. The fluid flow in the melt pool driven by thermal capillary convection and energy balance at liquid-vapor and solid-liquid interface was investigated and the impact of the droplets on the melt pool shape and ripple was studied. Dynamic motion, development of melt pool and the formation of cladding layer were simulated.


Sign in / Sign up

Export Citation Format

Share Document