Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaO

This paper discusses an experimental investigation into the fluidity of AZ91D-1 wt.% CaO magnesium melt via induction for thin-section investment casting. Plaster molds with thin spiral cavities (0.5 to 1.5 mm square sections) were designed and manufactured to assess the impact of casting conditions...

Full description

Saved in:
Bibliographic Details
Main Authors: V.H. Carneiro, V. Lopes, I. Duarte, H. Puga
Format: Article
Language:English
Published: KeAi Communications Co., Ltd. 2025-06-01
Series:Journal of Magnesium and Alloys
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2213956725001550
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849432228112629760
author V.H. Carneiro
V. Lopes
I. Duarte
H. Puga
author_facet V.H. Carneiro
V. Lopes
I. Duarte
H. Puga
author_sort V.H. Carneiro
collection DOAJ
description This paper discusses an experimental investigation into the fluidity of AZ91D-1 wt.% CaO magnesium melt via induction for thin-section investment casting. Plaster molds with thin spiral cavities (0.5 to 1.5 mm square sections) were designed and manufactured to assess the impact of casting conditions on filling length, as magnesium alloys cause severe melting and melt-mold exothermic reactions, making investment casting challenging. Combinations of traditional Mg-mold reaction mitigation techniques, such as applying a protective mold coating (Yttria) and vacuum, were examined to determine their role in the filling process. The results suggest that when induction is employed to melt reactive alloys, these methods are not always beneficial, as initially thought. Particularly at higher melt temperatures, the combination of Yttria-coated molds with low-pressure vacuum induction significantly reduce fluidity: vacuum induced melt levitation which promotes oxidation with the residual atmosphere; and Yttria-coating cracking due to thermal stress during the mold fabrication slows filling and promotes significant melt-mold reaction. This study shows that best results to investment cast thin-sections are obtained by avoiding both vacuum and protective coatings, providing a viable route for the precision manufacturing of stent biomedical devices.
format Article
id doaj-art-c9123a20437a4f2a8ba8bff8eaa7582a
institution Kabale University
issn 2213-9567
language English
publishDate 2025-06-01
publisher KeAi Communications Co., Ltd.
record_format Article
series Journal of Magnesium and Alloys
spelling doaj-art-c9123a20437a4f2a8ba8bff8eaa7582a2025-08-20T03:27:25ZengKeAi Communications Co., Ltd.Journal of Magnesium and Alloys2213-95672025-06-011362845285410.1016/j.jma.2025.04.028Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaOV.H. Carneiro0V. Lopes1I. Duarte2H. Puga3INESC TEC - Institute for Systems and Computer Engineering, Technology and Science, R. Dr. Roberto Frias, 4200-465 Porto, Portugal; Department of Engineering, School of Science and Technology - Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5001-801 Vila Real PortugalINL – International Iberian Nanotechnology Laboratory, Avenida Mestre José Veiga, 4715-330 Braga, Portugal; CMEMS-UMinho, Department of Mechanical Engineering, University of Minho, Campus de Azurém, 4800-058 Guimarães, PortugalTEMA - Centre for Mechanical Technology and Automation, Department of Mechanical Engineering, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; LASI - Intelligent Systems Associate Laboratory, Campus Azurém, 4800-058 Guimarães, PortugalCMEMS-UMinho, Department of Mechanical Engineering, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal; Corresponding author.This paper discusses an experimental investigation into the fluidity of AZ91D-1 wt.% CaO magnesium melt via induction for thin-section investment casting. Plaster molds with thin spiral cavities (0.5 to 1.5 mm square sections) were designed and manufactured to assess the impact of casting conditions on filling length, as magnesium alloys cause severe melting and melt-mold exothermic reactions, making investment casting challenging. Combinations of traditional Mg-mold reaction mitigation techniques, such as applying a protective mold coating (Yttria) and vacuum, were examined to determine their role in the filling process. The results suggest that when induction is employed to melt reactive alloys, these methods are not always beneficial, as initially thought. Particularly at higher melt temperatures, the combination of Yttria-coated molds with low-pressure vacuum induction significantly reduce fluidity: vacuum induced melt levitation which promotes oxidation with the residual atmosphere; and Yttria-coating cracking due to thermal stress during the mold fabrication slows filling and promotes significant melt-mold reaction. This study shows that best results to investment cast thin-sections are obtained by avoiding both vacuum and protective coatings, providing a viable route for the precision manufacturing of stent biomedical devices.http://www.sciencedirect.com/science/article/pii/S2213956725001550AZ91D-1 wt.% CAOFluidityInvestment castingYttria-coatingVacuum
spellingShingle V.H. Carneiro
V. Lopes
I. Duarte
H. Puga
Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaO
Journal of Magnesium and Alloys
AZ91D-1 wt.% CAO
Fluidity
Investment casting
Yttria-coating
Vacuum
title Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaO
title_full Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaO
title_fullStr Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaO
title_full_unstemmed Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaO
title_short Optimizing the fluidity in thin-section investment casting for vacuum induction molten AZ91D-1 wt.% CaO
title_sort optimizing the fluidity in thin section investment casting for vacuum induction molten az91d 1 wt cao
topic AZ91D-1 wt.% CAO
Fluidity
Investment casting
Yttria-coating
Vacuum
url http://www.sciencedirect.com/science/article/pii/S2213956725001550
work_keys_str_mv AT vhcarneiro optimizingthefluidityinthinsectioninvestmentcastingforvacuuminductionmoltenaz91d1wtcao
AT vlopes optimizingthefluidityinthinsectioninvestmentcastingforvacuuminductionmoltenaz91d1wtcao
AT iduarte optimizingthefluidityinthinsectioninvestmentcastingforvacuuminductionmoltenaz91d1wtcao
AT hpuga optimizingthefluidityinthinsectioninvestmentcastingforvacuuminductionmoltenaz91d1wtcao