Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets

Good metallurgical bonding between neighboring droplets is essential in droplet-based 3D printing. However, although the mechanism of remelting has clearly been mastered, cold laps are still common internal defects of formed parts in uniform aluminum droplets deposition manufacturing, which is due t...

Full description

Bibliographic Details
Main Authors: Yi, Hao, Qi, Lehua, Luo, Jun, Zhang, Daicong, Li, Hejun, Hou, Xianghui
Format: Article
Published: Elsevier 2018
Subjects:
Online Access:https://eprints.nottingham.ac.uk/52453/
_version_ 1848798729049473024
author Yi, Hao
Qi, Lehua
Luo, Jun
Zhang, Daicong
Li, Hejun
Hou, Xianghui
author_facet Yi, Hao
Qi, Lehua
Luo, Jun
Zhang, Daicong
Li, Hejun
Hou, Xianghui
author_sort Yi, Hao
building Nottingham Research Data Repository
collection Online Access
description Good metallurgical bonding between neighboring droplets is essential in droplet-based 3D printing. However, although the mechanism of remelting has clearly been mastered, cold laps are still common internal defects of formed parts in uniform aluminum droplets deposition manufacturing, which is due to the overlook of the surface morphologies of solidified droplets. Here, for the first time, the blocking effect of ripples and solidification angles on the fusion between droplets is revealed. To investigate the detailed process of remelting, a 3D numerical model was developed, basing on the volume of fluid (VOF) method. Experiments and simulations show that the remelting process between neighboring droplets can be divided into two stages according to the transient contact between the second droplet and the substrate. In the first stage, a non-intuitive result is observed that cold laps can also be formed even if the remelting conditions are satisfied in theory. Ripples on the surface of previously-deposited droplet block its direct contact with the new-coming droplet. In the second stage, cold laps on bottom surface are formed due to incomplete filling of liquid metal when the solidification angle is greater than 90°. Furthermore, these cold laps are difficult to be completely avoided by improving the temperature parameters. To address this problem, a novel strategy of decreasing the thermal conductivity coefficient of the substrate is proposed. This method effectively promotes remelting between droplets by eliminating ripples and decreasing solidification angles.
first_indexed 2025-11-14T20:24:24Z
format Article
id nottingham-52453
institution University of Nottingham Malaysia Campus
institution_category Local University
last_indexed 2025-11-14T20:24:24Z
publishDate 2018
publisher Elsevier
recordtype eprints
repository_type Digital Repository
spelling nottingham-524532020-05-04T19:50:35Z https://eprints.nottingham.ac.uk/52453/ Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets Yi, Hao Qi, Lehua Luo, Jun Zhang, Daicong Li, Hejun Hou, Xianghui Good metallurgical bonding between neighboring droplets is essential in droplet-based 3D printing. However, although the mechanism of remelting has clearly been mastered, cold laps are still common internal defects of formed parts in uniform aluminum droplets deposition manufacturing, which is due to the overlook of the surface morphologies of solidified droplets. Here, for the first time, the blocking effect of ripples and solidification angles on the fusion between droplets is revealed. To investigate the detailed process of remelting, a 3D numerical model was developed, basing on the volume of fluid (VOF) method. Experiments and simulations show that the remelting process between neighboring droplets can be divided into two stages according to the transient contact between the second droplet and the substrate. In the first stage, a non-intuitive result is observed that cold laps can also be formed even if the remelting conditions are satisfied in theory. Ripples on the surface of previously-deposited droplet block its direct contact with the new-coming droplet. In the second stage, cold laps on bottom surface are formed due to incomplete filling of liquid metal when the solidification angle is greater than 90°. Furthermore, these cold laps are difficult to be completely avoided by improving the temperature parameters. To address this problem, a novel strategy of decreasing the thermal conductivity coefficient of the substrate is proposed. This method effectively promotes remelting between droplets by eliminating ripples and decreasing solidification angles. Elsevier 2018-08 Article PeerReviewed Yi, Hao, Qi, Lehua, Luo, Jun, Zhang, Daicong, Li, Hejun and Hou, Xianghui (2018) Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets. International Journal of Machine Tools and Manufacture, 130-131 . pp. 1-11. ISSN 0890-6955 3D printing; Aluminum droplets; Metallurgical bonding; Ripples; Solidification angle https://www.sciencedirect.com/science/article/pii/S089069551830066X doi:10.1016/j.ijmachtools.2018.03.006 doi:10.1016/j.ijmachtools.2018.03.006
spellingShingle 3D printing; Aluminum droplets; Metallurgical bonding; Ripples; Solidification angle
Yi, Hao
Qi, Lehua
Luo, Jun
Zhang, Daicong
Li, Hejun
Hou, Xianghui
Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets
title Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets
title_full Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets
title_fullStr Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets
title_full_unstemmed Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets
title_short Effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets
title_sort effect of the surface morphology of solidified droplet on remelting between neighboring aluminum droplets
topic 3D printing; Aluminum droplets; Metallurgical bonding; Ripples; Solidification angle
url https://eprints.nottingham.ac.uk/52453/
https://eprints.nottingham.ac.uk/52453/
https://eprints.nottingham.ac.uk/52453/