scholarly journals A Comparative Analysis of Laser Additive Manufacturing of High Layer Thickness Pure Ti and Inconel 718 Alloy Materials Using Finite Element Method

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 876 ◽  
Author(s):  
Sapam Ningthemba Singh ◽  
Sohini Chowdhury ◽  
Yadaiah Nirsanametla ◽  
Anil Kumar Deepati ◽  
Chander Prakash ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Layer Thickness ◽  
Inconel 718 ◽  
Laser Power ◽  
Scanning Speed ◽  
Laser Additive Manufacturing ◽  
Inconel 718 Alloy ◽  
Melt Pool ◽  
High Layer

Investigation of the selective laser melting (SLM) process, using finite element method, to understand the influences of laser power and scanning speed on the heat flow and melt-pool dimensions is a challenging task. Most of the existing studies are focused on the study of thin layer thickness and comparative study of same materials under different manufacturing conditions. The present work is focused on comparative analysis of thermal cycles and complex melt-pool behavior of a high layer thickness multi-layer laser additive manufacturing (LAM) of pure Titanium (Ti) and Inconel 718. A transient 3D finite-element model is developed to perform a quantitative comparative study on two materials to examine the temperature distribution and disparities in melt-pool behaviours under similar processing conditions. It is observed that the layers are properly melted and sintered for the considered process parameters. The temperature and melt-pool increases as laser power move in the same layer and when new layers are added. The same is observed when the laser power increases, and opposite is observed for increasing scanning speed while keeping other parameters constant. It is also found that Inconel 718 alloy has a higher maximum temperature than Ti material for the same process parameter and hence higher melt-pool dimensions.

scholarly journals Study on the Numerical Simulation of the SLM Molten Pool Dynamic Behavior of a Nickel-Based Superalloy on the Workpiece Scale

Materials ◽  
2019 ◽  
Vol 12 (14) ◽  
pp. 2272 ◽  
Author(s):  
Liu Cao ◽  
Xuefeng Yuan
Keyword(s):  
Numerical Simulation ◽  
Dynamic Behavior ◽  
Inconel 718 ◽  
Molten Pool ◽  
Laser Power ◽  
Scanning Speed ◽  
Physical Parameters ◽  
Inconel 718 Alloy ◽  
Track Width ◽  
Nickel Based Superalloy

Nickel-based superalloys are one of the most industrially important families of metallic alloys at present. Selective Laser Melting (SLM), as one of the additive manufacturing technologies for directly forming complex metal parts, has been applied in the production of Inconel 718 components. Based on the more reasonable and comprehensive equivalent processing models (vaporization heat loss, equivalent physical parameters) for the nickel-based superalloy SLM process, an SLM molten pool dynamic behavior prediction model on the workpiece scale was established. Related equivalent processing models were customized by secondary development with the software Fluent. In order to verify the feasibility of the SLM molten pool dynamics model, the SLM single-pass employed to form the Inconel 718 alloy process was calculated. The simulated and experimental solidified track dimensions were in good agreement. Then, the influences of different process parameters (laser power, scanning speed) on the SLM formation of the Inconel 718 alloy were calculated and analyzed. The simulation and experimental solidified track widths were well-matched, and the result showed that, as a rule, the solidified track width increased linearly with the laser power and decreased linearly with the scanning speed. This paper will help lay the foundation for a subsequent numerical simulation study of the thermal-melt-stress evolution process of an SLM workpiece.

scholarly journals Effect of Layer-Wise Varying Parameters on the Microstructure and Soundness of Selective Laser Melted INCONEL 718 Alloy

Materials ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2165 ◽  
Author(s):  
Xiang Wang ◽  
Jinwu Kang ◽  
Tianjiao Wang ◽  
Pengyue Wu ◽  
Tao Feng ◽  
...  
Keyword(s):  
Energy Density ◽  
Inconel 718 ◽  
Laser Energy ◽  
Scanning Speed ◽  
High Energy ◽  
High Energy Density ◽  
Inconel 718 Alloy ◽  
Melt Pool ◽  
Columnar Grains ◽  
Melt Pool Size

Selective laser melting (SLM) is a promising powder bed fusion additive manufacturing technique for metal part fabrication. In this paper, varying scanning speed in the range of 500 mm/s to 1900 mm/s, and laser power in the range of 100 W to 200 W, were realized from layer to layer in a cycle of 56 layers in a single cuboid Inconel 718 alloy specimen through SLM. Layer-wise variation of microstructure and porosity were acquired, showing the layer-wise controlling capability of microstructural soundness. The melt pool size and soundness are closely linked with the energy input. High energy density led to sound regions with larger, orderly stacked melt pools and columnar grains, while low energy density resulted in porous regions with smaller, mismatched melt pools, un-melted powder, and equiaxed grains with finer dendrites. With the increase of laser energy density, the specimen shifts from porous region to sound region within several layers.

Research on Warpage of Polystyrene in Selective Laser Sintering

2010 ◽  
Vol 43 ◽  
pp. 578-582 ◽  
Author(s):  
C.Y. Wang ◽  
Q. Dong ◽  
X.X. Shen
Keyword(s):  
Layer Thickness ◽  
Process Parameters ◽  
Laser Power ◽  
Selective Laser Sintering ◽  
Scanning Speed ◽  
Laser Sintering ◽  
Main Process ◽  
Influence Of Process Parameters ◽  
Temperature Changes ◽  
Hatch Spacing

Warpage is a crucial factor to accuracy of sintering part in selective laser sintering (SLS) process. In this paper, The influence of process parameters on warpage when sintering polystyrene(PS) materials in SLS are investigated. The laser power, scanning speed, hatch spacing, layer thickness as well as temperature of powder are considered as the main process parameters. The results showed that warpage increases with the increase of hatch space. Contary to it, warpage decreases with the increase of laser power. Warpage decreases with the increase of layer thickness between 0.16~0.18mm and changes little with increase of the thickness. Warpage increases along with the increase of scanning speed but decreases when the speed is over about 2000mm/s. When the temperature changes between 82°C-86°C, warpage decreases little with the increase of temperature. But further increase of temperature leads to warpage decreasing sharply when the temperature changes between 86°C-90°C.

Multi-scale simulation approach for identifying optimal parameters for fabrication ofhigh-density Inconel 718 parts using selective laser melting

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hong-Chuong Tran ◽  
Yu-Lung Lo ◽  
Trong-Nhan Le ◽  
Alan Kin-Tak Lau ◽  
Hong-You Lin
Keyword(s):  
Laser Power ◽  
Scanning Speed ◽  
Processing Conditions ◽  
Simulation Framework ◽  
Content Type ◽  
Process Maps ◽  
Multi Scale ◽  
Melt Pool ◽  
Optimal Processing ◽  
Input Design

Purpose Depending on an experimental approach to find optimal parameters for producing fully dense (relative density > 99%) Inconel 718 (IN718) components in the selective laser melting (SLM) process is expensive and offers no guarantee of success. Accordingly, this study aims to propose a multi-scale simulation framework to guide the choice of processing parameters in a more pragmatic manner. Design/methodology/approach In the proposed approach, a powder layer, ray tracing and heat transfer simulation models are used to calculate the melt pool dimensions and evaporation volume corresponding to a small number of laser power and scanning speed conditions within the input design space. A layer-heating model is then used to determine the inter-layer idle time required to maximize the temperature convergence rate of the solidified layer beneath the power bed. The simulation results are used to train surrogate models to construct SLM process maps for 3,600 pairs of the laser power and scanning speed within the input design space given three different values of the underlying solidified layer temperature (i.e., 353 K, 673 K and 873 K). The ideal selection of laser power and scanning speed of each process map is chosen based on four quality-related criteria listed as follows: without the appearance of key-hole melting; an evaporation volume less than the volume of the d90 powder particles; ensuring the stability of single scan tracks; and avoiding a weak contact between the melt pool and substrate. Finally, the optimal laser power and scanning speed parameters for the SLM process are determined by superimposing the optimal regions of the individual process maps. Findings The feasibility of the proposed approach is demonstrated by fabricating IN718 test specimens using the optimal processing conditions identified by the simulation framework. It is shown that the maximum density of the fabricated parts is 99.94%, while the average density is 99.88% and the standard deviation is less than 0.05%. Originality/value The present study proposed a multi-scale simulation model which can efficiently predict the optimal processing conditions for producing fully dense components in the SLM process. If the geometry of the three-dimensional printed part is changed or the machine and powder material is altered, users can use the proposed method for predicting the processing conditions that can produce the high-density part.

scholarly journals Parametric Study on In Situ Laser Powder Bed Fusion of Mo(Si1−x,Alx)2

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4849
Author(s):  
T. Minasyan ◽  
S. Aydinyan ◽  
E. Toyserkani ◽  
I. Hussainova
Keyword(s):  
Parametric Study ◽  
Laser Power ◽  
Side Surface ◽  
Scanning Speed ◽  
Processing Parameters ◽  
Powder Bed ◽  
Good Surface ◽  
Melt Pool ◽  
Scan Speed ◽  
Good Surface Finish

Mo(Si1−x,Alx)2 composites were produced by a pulsed laser reactive selective laser melting of MoSi2 and 30 wt.% AlSi10Mg powder mixture. The parametric study, altering the laser power between 100 and 300 W and scan speed between 400 and 1500 mm·s−1, has been conducted to estimate the effect of processing parameters on printed coupon samples’ quality. It was shown that samples prepared at 150–200 W laser power and 400–500 mm·s−1 scan speed, as well as 250 W laser power along with 700 mm·s−1 scan speed, provide a relatively good surface finish with 6.5 ± 0.5 µm–10.3 ± 0.8 µm roughness at the top of coupons, and 9.3 ± 0.7 µm–13.2 ± 1.1 µm side surface roughness in addition to a remarkable chemical and microstructural homogeneity. An increase in the laser power and a decrease in the scan speed led to an apparent improvement in the densification behavior resulting in printed coupons of up to 99.8% relative density and hardness of ~600 HV1 or ~560 HV5. The printed parts are composed of epitaxially grown columnar dendritic melt pool cores and coarser dendrites beyond the morphological transition zone in overlapped regions. An increase in the scanning speed at a fixed laser power and a decrease in the power at a fixed scan speed prohibited the complete single displacement reaction between MoSi2 and aluminum, leading to unreacted MoSi2 and Al lean hexagonal Mo(Si1−x,Alx)2 phase.

Finite element simulation of machining Inconel 718 alloy including microstructure changes

2014 ◽  
Vol 88 ◽  
pp. 110-121 ◽  
Author(s):  
F. Jafarian ◽  
M. Imaz Ciaran ◽  
D. Umbrello ◽  
P.J. Arrazola ◽  
L. Filice ◽  
...  
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Inconel 718 ◽  
Inconel 718 Alloy ◽  
Microstructure Changes ◽  
Element Simulation

scholarly journals Influence of Melt-Pool Stability in 3D Printing of NdFeB Magnets on Density and Magnetic Properties

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 139 ◽  
Author(s):  
Mateusz Skalon ◽  
Michael Görtler ◽  
Benjamin Meier ◽  
Siegfried Arneitz ◽  
Nikolaus Urban ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Layer Thickness ◽  
Process Parameters ◽  
Permanent Magnets ◽  
Scanning Speed ◽  
Maximum Energy ◽  
Powder Layer ◽  
Influence Of Process Parameters ◽  
Layer Height ◽  
Melt Pool

The current work presents the results of an investigation focused on the influence of process parameters on the melt-track stability and its consequence to the sample density printed out of NdFeB powder. Commercially available powder of Nd7.5Pr0.7Fe75.4Co2.5B8.8Zr2.6Ti2.5 alloy was investigated at the angle of application in selective laser melting of permanent magnets. Using single track printing the stability of the melt pool was investigated under changing process parameters. The influence of changing laser power, scanning speed, and powder layer thickness on density, porosity structure, microstructure, phase composition, and magnetic properties were investigated. The results showed that energy density coupled with powder layer thickness plays a crucial role in melt-track stability. It was possible to manufacture magnets of both high relative density and high magnetic properties. Magnetization tests showed a significant correlation between the shape of the demagnetization curve and the layer height. While small layer heights are beneficial for sufficient magnetic properties, the remaining main parameters tend to affect the magnetic properties less. A quasi-linear correlation between the layer height and the magnetic properties remanence (Jr), coercivity (HcJ) and maximum energy product ((BH)max) was found.

Sign in / Sign up

Export Citation Format

Share Document