Fabrication of graphene-based master alloys for the development of B319 aluminum alloy-graphene composites with enhanced tribological properties
department or school: Applied Science, Faculty of
department or school: Engineering, School of (Okanagan)
data provider: DSpace
degree campus: UBCO
creator: Pillari, Lava Kumar
issued: 2024-07-03T09:22:32Z
issued: 2024
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: The automotive industry is globally transitioning towards lighter vehicles to meet stringent fuel standards and reduce CO₂ emissions. The B319 aluminum (Al) alloy finds widespread use in automotive powertrain components due to its low density, good strength, and excellent castability. However, the poor tribological properties of the B319 Al alloy hinder its broader application in powertrain components. Graphene has been considered a promising reinforcement for Al matrices due to its ability to enhance multiple properties simultaneously while maintaining the lightweight characteristics of the alloy. However, graphene agglomeration and its poor wettability pose significant processing challenges, particularly in the casting process, thereby limiting the advancement of Al-graphene composites and their industrial adoption. Therefore, this study aims to fabricate B319 Al alloy-graphene (0-0.7 wt.%) composites utilizing a novel distribution approach. This approach involves the fabrication of composite master alloy (F357-5 wt.% graphene) through a flake powder metallurgy approach involving ball milling and spark plasma sintering. Subsequently, the composite master alloy was introduced into the B319 Al alloy melt to fabricate B319-graphene composites via stir casting. The effect of graphene on the microstructure, hardness, tribological behavior, electrical conductivity, and thermal conductivity of the B319 Al alloy was investigated. The results indicate that the addition of graphene decreased the grain size of the B319 Al alloy, primarily attributed to the additional nucleation sites provided by the presence of graphene. Moreover, adding graphene refined the Si phase and changed its morphology from a needle-like to a more fibrous structure. Consequently, the hardness of B319 Al alloy was enhanced by 20% with the addition of 0.1 wt.% graphene, but it deteriorated with graphene additions beyond 0.3 wt.%. Regardless of the load, the B319-0.3 wt.% graphene composite exhibited th…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/88556
note: FABRICATION OF GRAPHENE-BASED MASTER ALLOYS FOR THE DEVELOPMENT OF B319 ALUMINUM ALLOY-GRAPHENE COMPOSITES WITH ENHANCED TRIBOLOGICAL PROPERTIES by Lava Kumar Pillari B.Tech, Rajiv Gandhi University of Knowledge Technologies-Nuzvid, India, 2014 M.Tech (By Research), Vellore Institute of Technology-Chennai, India, 2018 A DISSERTATION SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE COLLEGE OF GRADUATE STUDIES (Mechanical Engineering) THE UNIVERSITY OF BRITISH COLUMBIA (Okanagan) June 2024 © Lava Kumar Pillari, 2024 ii The following individuals certify that they have read, and recommend to the College of Graduate Studies for acceptance, a dissertation entitled: Fabrication of Graphene-Based Master Alloys for the Development of B319 Aluminum Alloy-Graphene Composites with Enhanced Tribological Properties submitted by Lava Kumar Pillari in partial fulfillment of the requirements of the degree of Doctor of Philosophy . Dr. Lukas Bichler, School of Engineering, UBC Okanagan Supervisor Dr. Mohammad Arjmand, School of Engineering, UBC Okanagan Supervisory Committee Member Dr. Jian Liu, School of Engineering, UBC Okanagan Supervisory Committee Member Dr. Kasun Hewage, School of Engineering, UBC Okanagan University Examiner Dr. Gobinda Saha, Mechanical Engineering, University of New Brunswick External Examiner iii Abstract The automotive industry is globally transitioning towards lighter vehicles to meet stringent fuel standards and reduce CO2 emissions. The B319 aluminum (Al) alloy finds widespread use in automotive powertrain components due to its low density, good strength, and excellent castability. However, the poor tribological properties of the B319 Al alloy hinder its broader application in powertrain components. Graphene has been considered a promising reinforcement for Al matrices due to its ability to enhance multiple properties simultaneously while maintaining the lightweight characteristics of the alloy. However, …
has type: Thesis/Dissertation
date issued: 2024-09
is shown at: 10.14288/1.0444064
language: eng
degree discipline: Mechanical Engineering
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Lukas, Bichler
type: Text
identifier URI: http://hdl.handle.net/2429/88556