Modeling and simulation of the columnar-to-equiaxed transition during laser melting deposition of Invar alloy

Zhan, Xiaohong; Lin, Xin; Gao, Zhuanni; Qi, Chaoqi; Zhou, Junjie; Gu, Dongdong

doi:10.1016/j.jallcom.2018.04.313

Cited by 57 publications

(9 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 6B shows that the cellulars were mostly pentagonal in shape and the grain size was small. There were cellulars at the top, center and boundary of the molten pool, which were distributed randomly (Zhang et al, 2018). However, most of the cellulars were located at the top and in the center of the molten pool rather than the boundary.…”

Section: Microstructurementioning

confidence: 99%

Effects of laser energy density on morphology features and microstructures of the single molten track in selective laser melting

Wang

Liu

et al. 2023

Front. Mater.

View full text Add to dashboard Cite

Single molten track (SMT) is the basic unit of the selective laser melting (SLM) process, of which the morphology features and microstructures have great significance on the molding quality. In this study, the effects of laser energy density (LED) on characteristics of SMT were studied with 316 L stainless steel processing by SLM. The results indicate that an optimized range of LED was between 200 and 500 J/mm3, which was the best for SLM process of 316 L leading to beautiful SMT appearance such as continuous uniform water-ridge-like surface, good contour straightness, smooth edges, little adhesive powder, and high densification. The microstructures of the SMT molten pool are mainly composed of equiaxed cellular and columnar dendrites. As the LED decreased, the cellular became smaller and disappeared, while the length and width of columnar crystals even gradually increased. The size of the cellular varies between 0.43 and 1.70 μm with the LEDs increase. The relationship between SMT characteristics and LED found in this work can be readily used to optimize SMT and control the microstructures in situ, and the laser energy density range that the work has identified will simplify most of the guess work in additive manufacturing.

show abstract

Section: Microstructurementioning

confidence: 99%

Effects of laser energy density on morphology features and microstructures of the single molten track in selective laser melting

Wang

Liu

et al. 2023

Front. Mater.

View full text Add to dashboard Cite

show abstract

“…Sawant et al [ 7 ] presented a finite element model to predict the dilution of single-track deposition in different process parameters. Zhan et al [ 8 ] and Xie et al [ 9 ] predicted the temperature of single-track deposition and analyzed microstructure evolution with the CA-FE model. Du et al [ 10 ] researched the temperature gradient and solidification growth rate in molten pools, and they also studied the influence of solidification microstructure on these factors.…”

Section: Introductionmentioning

confidence: 99%

Thermal and Mechanical Variation Analysis on Multi-Layer Thin Wall during Continuous Laser Deposition, Continuous Pulsed Laser Deposition, and Interval Pulsed Laser Deposition

Kong

Liang

et al. 2022

Materials

View full text Add to dashboard Cite

Direct laser deposition (DLD) is widely used in precision manufacturing, but the process parameters (e.g., laser power, scanning patterns) easily lead to changes in dimensional accuracy and structural properties. Many methods have been proposed to analyze the principle of distortion and residual stress generation, but it is difficult to evaluate the involvement of temperature and stress in the process of rapid melting and solidification. In this paper, a three-dimensional finite element model is established based on thermal–mechanical relationships in multilayer DLD. Differences in temperature and residual stress between continuous laser deposition (CLD) and pulsed laser deposition (PLD) are compared with the numerical model. To validate the relationship, the temperature and residual stress values obtained by numerical simulation are compared with the values obtained by the HIOKI-LR8431 temperature logger and the Pulstec μ-X360s X-ray diffraction (XRD) instrument. The results indicate that the temperature and residual stress of the deposition part can be evaluated by the proposed simulation model. The proposed PLD process, which includes continuous pulsed laser deposition (CPLD) and interval pulsed laser deposition (IPLD), were found more effective to improve the homogeneity of temperature and residual stress than the CLD process. This study is expected to be useful in the distortion control and microstructure consistency of multilayer deposited parts.

show abstract

“…The heat accumulation effect is a long-lasting challenge in controlling the multi-pass cladding process [10,11]. The low temperature of the substrate at the initial stage leads to less energy absorption and a small dilution ratio [12].…”

Section: Introductionmentioning

confidence: 99%

Deep-learning Driven Precision Control of Dilution Rate in Multi-pass Laser Cladding: Experiment and Simulation

Zhu

Xia²,

Kamali³

et al. 2022

Preprint

View full text Add to dashboard Cite

The continuous energy input can lead to heat accumulation in the multi-pass lap laser cladding, which results in a progressive increase in the dilution rate and deteriorates the quality of laser cladding. Precisely controlling the stability of the dilution in the multi-pass laser cladding is still challenging. In this study, we proposed a deep-learning driven method for precisely controlling the dilution rate in the multi-pass laser cladding. Initially, the relationship between the dilution rate and power energy is retracted via the experiment-based finite element simulation. Subsequently, the convolution neural network deep learning is applied to optimise and improve the accuracy of the dilution rates in the cladding layer. The experiment verifies that the high stability of dilution rate in each pass, i.e. average errors of less than 10.88%, is achieved via in-situ adjusting of the power energy using the prediction obtained from the proposed method. We also attempted to provide insights into the dilution mechanism in Invar alloy multi-pass laser cladding as well as the potential applications of this method for other materials in the cladding and other 3D metal additive manufacturing.

show abstract

Modeling and simulation of the columnar-to-equiaxed transition during laser melting deposition of Invar alloy

Cited by 57 publications

References 23 publications

Effects of laser energy density on morphology features and microstructures of the single molten track in selective laser melting

Effects of laser energy density on morphology features and microstructures of the single molten track in selective laser melting

Thermal and Mechanical Variation Analysis on Multi-Layer Thin Wall during Continuous Laser Deposition, Continuous Pulsed Laser Deposition, and Interval Pulsed Laser Deposition

Deep-learning Driven Precision Control of Dilution Rate in Multi-pass Laser Cladding: Experiment and Simulation

Contact Info

Product

Resources

About