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- Tamil Alagan, Nageswaran, 1990-, et al.
(författare)
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Effects of high pressure cooling in the flank and rake faces of WC tool on the tool wear mechanism and process conditions in turning of alloy 718
- 2019
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Ingår i: Wear. - : Elsevier BV. - 0043-1648 .- 1873-2577. ; 434-435
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Tidskriftsartikel (refereegranskat)abstract
- The exceptional properties of Heat Resistant Super Alloys (HRSA) justify the search for advanced technologiesthat can improve the capability of machining these materials. One such advanced technology is the applicationof a coolant at high pressure while machining, a strategic solution known for at least six decades. The aim is toachieve extended tool life, better chip control and improved surface finish. Another aim is to control the temperature in the workpiece/tool interface targeting for optimum cutting conditions. In most of the existing applications with high-pressure coolant media, the nozzles are positioned on the rake face side of the insert andthey are directed towards the cutting edge (the high-temperature area). The coolant is applied at high-pressureto improve the penetration of the cooling media along the cutting edge in the interface between the insert andworkpiece material (chip) as well as to increase chip breakability. However, the corresponding infusion ofcoolant media in the interface between the flank face of the insert and the work material (tertiary shear zone) hasbeen previously only scarcely addressed, as is the combined effect of coolant applications on rake and clearancesides of the insert. The present work addresses the influence of different pressure conditions in (flank: 0, 4 and8 MPa; rake: 8 and 16 MPa) on maximum flank wear, flank wear area, tool wear mechanism, and overall processperformance. Round uncoated inserts are used in a set of face turning experiments, conducted on the widely usedHRSA "Alloy 718" and run in two condition tests with respect to cutting speed (45 (low) and 90 (high) m/min).The results show that an increase in rake pressure from 8 to 16 MPa has certainly a positive impact on tool life.Furthermore, at higher vc of 90 m/min, cutting edge deterioration: due to an extensive abrasion and crack in thewear zone were the dominant wear mechanism. Nevertheless, the increase in coolant pressure condition to16 MPa reduced the amount of abrasion on the tool compared to 8 MPa. At the lower cutting speed, no crack orplastic deformation or extensive abrasion were found. When using 8 MPa pressure of coolant media on the flank,the wear was reduced by 20% compared to flood cooling conditions. Application of high-pressure cooling on theflank face has a positive effect on tool life and overall machining performance of Alloy 718.
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