Please use this identifier to cite or link to this item:
Full metadata record
DC FieldValueLanguage
dc.contributor.authorLee, Boon Yaoen_US
dc.identifier.citationLee, B. Y. (2021). Additive manufacturing of high Si aluminium alloys. Final Year Project (FYP), Nanyang Technological University, Singapore.
dc.description.abstractThe effects of laser power variation and post additive manufactured (AM) heat treatment on the microstructure of primary silicon phase and mechanical properties have been studied in this paper. This observation was done through optical microscope and Vickers hardness testing. It was discovered that primary silicon microstructure improves with increasing laser power. As the higher laser power provides more nucleating sites which resulted in smaller primary silicon phase particles. Beyond 800 W laser setting, the columnar primary silicon particles transform into a blocky morphology that reduces in effective diameter with increasing laser power. By increasing laser power from 800 W to 1900 W, the primary silicon diameter decreases by 84%, which shows significant microstructure improvement at higher power setting. However, the eutectic silicon phase at various laser power exhibits no significant microstructural change. At 800 W and 1350 W lower power settings it was observed that defects such as porosity and cracking appeared more frequently and is predominantly occurring near the melt pool surface. It is discovered that at 1900 W power setting, the deposit exhibit homogenous hardness at 180 HV, While the 1350 W and 800 W displayed decreasing hardness value towards the melt pool surface. To reduce the occurrence of defects, heat treatment at 300 ℃ to 500 ℃ proved to be successful in preventing defect occurrence by thermal stress relieving during the heat treatment process. From 400 ℃ heat treatment temperature onwards, spheroidization of eutectic silicon was observed. At 400 ℃ heat treatment onwards, there is a transformation of dendritic eutectic silicon into a composite like silicon reinforced aluminium matrix that surrounds the primary silicon phase. It is discovered that at all heat treatment temperature, the deposit exhibit homogenous hardness across the height of the melt pool. It is determined that 300 ℃ heat treatment temperature produces the best hardness result at ~155 HV.en_US
dc.publisherNanyang Technological Universityen_US
dc.subjectEngineering::Aeronautical engineeringen_US
dc.titleAdditive manufacturing of high Si aluminium alloysen_US
dc.typeFinal Year Project (FYP)en_US
dc.contributor.supervisorZhou Weien_US
dc.contributor.schoolSchool of Mechanical and Aerospace Engineeringen_US
dc.description.degreeBachelor of Engineering (Aerospace Engineering)en_US
item.fulltextWith Fulltext-
Appears in Collections:MAE Student Reports (FYP/IA/PA/PI)
Files in This Item:
File Description SizeFormat 
B111_Final Year Project Report.pdf
  Restricted Access
2.53 MBAdobe PDFView/Open

Page view(s)

Updated on Jun 28, 2022

Download(s) 50

Updated on Jun 28, 2022

Google ScholarTM


Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.