Cover Image

Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite

The current study investigated the effects of gadolinium (Gd) addition (0, 0.3, 0.5, 1.0, and 2.0 wt%) on microstructural development and solidification characteristics of hypereutectic Al-15%Mg2Si in-situ composite. Microstructural examinations were carried out via optical microscopy (OM), scanning...

Full description

Saved in:
Bibliographic Details
Main Authors: Ghandvar, Hamidreza, Idris, Mohd. Hasbullah, Ahmad, Norhayati, Emamy, Massoud
Format: Article
Published: Elsevier Inc. 2018
Subjects:
TJ Mechanical engineering and machinery
Online Access:http://eprints.utm.my/id/eprint/86317/
http://dx.doi.org/10.1016/j.matchar.2017.10.018
Tags: Add Tag
No Tags, Be the first to tag this record!
id my.utm.86317
record_format eprints
spelling my.utm.863172020-08-31T13:57:43Z http://eprints.utm.my/id/eprint/86317/ Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite Ghandvar, Hamidreza Idris, Mohd. Hasbullah Ahmad, Norhayati Emamy, Massoud TJ Mechanical engineering and machinery The current study investigated the effects of gadolinium (Gd) addition (0, 0.3, 0.5, 1.0, and 2.0 wt%) on microstructural development and solidification characteristics of hypereutectic Al-15%Mg2Si in-situ composite. Microstructural examinations were carried out via optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD). The results showed that an addition of 1.0 wt% Gd, changed the morphology of primary Mg2Si from coarse dendritic to fine truncated octahedral shape. Furthermore, the average size of primary Mg2Si particles decreased from 40 μm to 20 μm and density increased from 495 to 1167 particles/mm2. Besides that, cooling curve thermal analysis (CCTA) technique revealed that Gd addition increased nucleation and growth temperatures of primary Mg2Si phase. It is proposed that modification and refinement mechanism of Gd addition are mainly attributed to formation of tiny Al3Gd particles as the heterogeneous nucleation substrates for primary Mg2Si, which results in a refined distribution of these particles and poisoning effect by adsorbing Gd atoms, preferentially on {100} facets of Mg2Si crystals. Moreover, it is believed that formation of Gd intermetallic compounds is responsible for refinement of primary Mg2Si particles. Elsevier Inc. 2018-01 Article PeerReviewed Ghandvar, Hamidreza and Idris, Mohd. Hasbullah and Ahmad, Norhayati and Emamy, Massoud (2018) Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite. Materials Characterization, 135 . pp. 57-70. ISSN 1044-5803 http://dx.doi.org/10.1016/j.matchar.2017.10.018
institution Universiti Teknologi Malaysia
building UTM Library
collection Institutional Repository
continent Asia
country Malaysia
content_provider Universiti Teknologi Malaysia
content_source UTM Institutional Repository
url_provider http://eprints.utm.my/
topic TJ Mechanical engineering and machinery
spellingShingle TJ Mechanical engineering and machinery
Ghandvar, Hamidreza
Idris, Mohd. Hasbullah
Ahmad, Norhayati
Emamy, Massoud
Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite
description The current study investigated the effects of gadolinium (Gd) addition (0, 0.3, 0.5, 1.0, and 2.0 wt%) on microstructural development and solidification characteristics of hypereutectic Al-15%Mg2Si in-situ composite. Microstructural examinations were carried out via optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD). The results showed that an addition of 1.0 wt% Gd, changed the morphology of primary Mg2Si from coarse dendritic to fine truncated octahedral shape. Furthermore, the average size of primary Mg2Si particles decreased from 40 μm to 20 μm and density increased from 495 to 1167 particles/mm2. Besides that, cooling curve thermal analysis (CCTA) technique revealed that Gd addition increased nucleation and growth temperatures of primary Mg2Si phase. It is proposed that modification and refinement mechanism of Gd addition are mainly attributed to formation of tiny Al3Gd particles as the heterogeneous nucleation substrates for primary Mg2Si, which results in a refined distribution of these particles and poisoning effect by adsorbing Gd atoms, preferentially on {100} facets of Mg2Si crystals. Moreover, it is believed that formation of Gd intermetallic compounds is responsible for refinement of primary Mg2Si particles.
format Article
author Ghandvar, Hamidreza
Idris, Mohd. Hasbullah
Ahmad, Norhayati
Emamy, Massoud
author_facet Ghandvar, Hamidreza
Idris, Mohd. Hasbullah
Ahmad, Norhayati
Emamy, Massoud
author_sort Ghandvar, Hamidreza
title Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite
title_short Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite
title_full Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite
title_fullStr Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite
title_full_unstemmed Effect of gadolinium addition on microstructural evolution and solidification characteristics of Al-15%Mg2Si in-situ composite
title_sort effect of gadolinium addition on microstructural evolution and solidification characteristics of al-15%mg2si in-situ composite
publisher Elsevier Inc.
publishDate 2018
url http://eprints.utm.my/id/eprint/86317/
http://dx.doi.org/10.1016/j.matchar.2017.10.018
_version_ 1677781160723218432
score 13.211869

Similar Items