Yuewei Ai's research while affiliated with Huazhong University of Science and Technology and other places

Publications (14)

Article
High power laser welding is as an ideal advanced technology for joining the thick steel plates with high efficiency in the industries. This paper proposes a 3D numerical simulation modeling method to investigate keyhole profile characteristics and the effect of keyhole evolution on the molten pool, and understand weld formation process and defect g...
Article
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The effects of Mg back-diffusion on liquid channel segregation and morphology, and hence on the solidification cracking susceptibility (SCS) of Al-4.0 wt% Mg alloy, were investigated using phase-field simulations using a multistep computational strategy. We demonstrated that Mg back-diffusion can strongly reduce liquid channel segregation and facil...
Article
High power and high speed laser welding is as an attractive way to achieve the higher productivity in practical production. The weld periodical appearance defect, humping, is frequently generated in the high speed welding process. The weld quality is sequentially deteriorated severely due to the formed humping defect, which greatly limits the impro...
Article
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A modified non-equilibrium cellular automaton (CA) model is proposed to simulate the dendrite growth along the fusion boundary under transient conditions during the solidification process of laser beam welding (LBW) pool. The main non-equilibrium solidification effects, including solute trapping, deviation of the liquidus line slope, and kinetic un...
Article
Full-text available
This paper proposes an integrated method for process parameters optimization and objective analysis in the fiber laser keyhole welding based on Taguchi and finite element method (FEA). The Taguchi-FEA framework is established and applied for the objective of increasing the ratio of weld penetration to width (P/W) in the welded joints. Numerical sim...
Article
The weld geometry characteristics are highly related to the mechanical properties and performance of the joints. The top surface of the weld is often assumed as the flat surface during calculating the fluid flow in the molten pool and hence weld reinforcement is ignored among the geometric parameters. In this paper, a three-dimensional numerical si...
Article
The quality of the welded joints is greatly affected by the appearance and geometry of the weld bead. Understanding the formation mechanism of whole weld bead has great theoretical significance and engineering value. This paper proposes a novel three-dimensional model considering the heat transfer, keyhole free surface, surface tension and recoil p...
Article
Dissimilar materials welded joints provide many advantages in power, automotive, chemical, and spacecraft industries. The weld bead integrity which is determined by process parameters plays a significant role in the welding quality during the fiber laser welding (FLW) of dissimilar materials. In this paper, an optimization method by taking the inte...
Article
Full-text available
Laser welding has been widely used in automotive, power, chemical, nuclear and aerospace industries. The quality of welded joints is closely related to the existing defects which are primarily determined by the welding process parameters. This paper proposes a defects optimization method that takes the formation mechanism of welding defects and wel...
Article
Laser butt welding (LBW) of dissimilar materials has received great attention in automotive, power, chemical, nuclear and aerospace industries. The quality of welded joints is significantly affected by the generated defects in the dissimilar materials welding process. This paper proposes a defect-reducing optimization method that considers the geom...
Article
The welded joints of dissimilar materials have been widely used in automotive, ship and space industries. The joint quality is often evaluated by weld seam geometry, microstructures and mechanical properties. To obtain the desired weld seam geometry and improve the quality of welded joints, this paper proposes a process modeling and parameter optim...

Citations

... The application of GA is very famous in manufacturing sector. Ai et al. (2015) predict welding defects in laser butt welding of dissimilar materials by means of particle swarm optimization and back propagation neural network to establish the mathematical model of the welding process while a genetic algorithm is successfully tested to solve the model . The same authors proposed the use of radial basis function neural networks with GA to model the hole geometry in the same manufacturing process (Ai et al., 2015), showing the capabilities of GA to work on different kind of neural networks. ...
... The penetration state is closely related to the heat input during the welding process (Ai et al., 2018), which can be reflected by the status of the keyhole and molten pool (Gu et al., 2020;Wang & Li, 2013). Consequently, the penetration state can be judged by monitoring the morphological changes of the keyhole and molten pool. ...
... The most common way of optimizing the laser welding process is by choosing the right laser type for the application and then controlling and adjusting the rate of energy input to the workpiece by changing laser power and welding speed [6]. Without proper optimization, the laser welded joints can have significant external and internal defects such as spattering [10], porosity [11], weld humping [12], weld concavity [13], and weld undercut [14]. These defects are widely recognized to adversely affect the mechanical performance of the joint. ...
... There are several well-established methods such as cellular automata method [5][6][7][8][9], lattice Boltzmann method [10][11][12][13][14], level set method [15][16][17][18] and phase field method [19][20][21][22][23][24][25] which are used to simulate microscale solidification. Recently, the enthalpy method has gained popularity due to simplicity in formulation for modelling both macroscale [26][27][28][29][30][31] and microscale solidification [32][33][34][35][36][37][38][39][40][41][42][43]. ...
... In order to obtain the transient thermal conditions during laser welding, a three-dimensional transient heat transfer model is used to predict the thermal field. The governing equations and boundary conditions are available in References [25][26][27]. A moving hybrid heat source consisting of a double ellipsoid heat source and a linear attenuation peak Gaussian heat source was employed in this study, and its formulas can be found in our previous papers [26,28]. ...
... Since, the weld penetration and width of SS 316L weldment remains almost constant in transition phase regardless of increase in arc power for constant welding speed. This phenomenon is primarily due to imbalance in forces between surface tension force and vapour pressure of SS 316L alloying elements [31]. Figure 2 presents the weld penetration variation with respect to interaction energy per unit volume. ...
... The multiple sensing system which included six different sensors [189]. depth-width ratio of the weld seam, Ai et al. [207] applied the Taguchi method to optimize three welding parameters, i.e. the laser power, welding speed and focal position. Results showed the reliability and effectiveness of the proposed method. ...
... laser power, welding speed) or sensor data (e.g. light intensity) to predict quality values such as the tensile strength , weld bead dimensions (Ai et al., 2016;Lei et al., 2019) , residual stress (Dhas & Kumanan, 2014) or to classify quality types captured with camera images . Similar approaches were conducted in spot welding (Hamidinejad et al., 2012;Martín et al., 2016) and ultrasonic welding (Li et al., 2020b;Natesh et al., 2019) . ...
... The use of Artificial Neural Networks (ANNs) has been extensively used in many engineering applications to model complex systems (Ai et al., 2015). Recent developments in Convolutional Neural Networks (CNNs) have made possible the effective use of machine learning techniques in interacting with 2D data. ...