Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.767587
Title: Hybrid cooling/lubricating strategies for machining Ti-6Al-4V in CNC end milling
Author: Al-Samarrai, Ihsan
ISNI:       0000 0004 7660 1398
Awarding Body: University of Bath
Current Institution: University of Bath
Date of Award: 2018
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Abstract:
Titanium and its alloys are widely used in various engineering applications such as aerospace, biomedical and chemical industries due to their excellent combination of high strength-to weight ratio and good creep, corrosion and fracture resistance. However, these desirable design properties pose a serious challenge to the manufacturing engineers owing to the high temperatures and stresses generated during the machining of titanium alloys. The extremely low thermal conductivity of titanium alloys results in concentration of high temperature close to the tool cutting edge resulting in accelerated thermochemical and mechanical tool wear. Many cooling and lubricating techniques such as high pressure cooling (HPC), minimum quantity lubrication (MQL) and cryogenic machining have been proposed for improving the machinability of titanium alloys. In this study, a hybrid combination of MQL and cryogenic cooling using liquid nitrogen (LN2) is proposed, designed and manufactured as an innovative cooling/lubricating approach for CNC end milling of Ti-6Al-4V titanium alloy. The machining performance of the new hybrid cooling/lubrication technique is investigated in terms of tool wear and surface finish and compared to that of flood cooling, MQL and cryogenic cooling. The proposed hybrid cooling/lubrication technique demonstrated the best machining performance among all cooling/lubricating conditions and recorded more the 30 fold increased tool life over conventional flood cooling. In addition, 28% reduction in surface roughness was recorded for hybrid cooling/lubrication method as compared to flood cooling. The improvement in surface roughness was 50% for MQL when compared to flood cooling. The outstanding improvement in tool life with hybrid cooling/lubricating strategies is encouraging for the wide spread of this cooling/lubricating technique for industrial adoption.
Supervisor: Shokrani Chaharsooghi, Alborz ; Newman, Stephen Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.767587  DOI: Not available
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