Coolant boiling and cavitation wear – a new tool wear mechanism on WC tools in machining alloy 718 with high-pressure coolant
Artikel i vetenskaplig tidskrift, 2020
Concurrently, these achievements have revealed a knowledge gap and unlocked a new research area in understanding the effects and influences of coolant media applied on super-heated surfaces under high-pressure conditions. The aim of this study is to investigate the “coolant boiling and cavitation” phenomena that emerges during the application of coolant under high-pressure to the flank face of an uncoated WC tool while turning Alloy 718. The experimental campaign was conducted in three aspects: varying flank (coolant media) pressure; varying spiral cutting length (SCL); and varying cutting speed.
The results revealed that the location and size of the coolant-boiling region correlated with flank wear, coolant pressure and vapour pressure of the coolant at the investigated pressure levels. Further, the results showed that coolant applied with a lower pressure than the vapour pressure of the coolant itself caused the “Leidenfrost” effect. This then acts as a coolant media barrier and effectively reduces the heat transport from the cutting zone.
Further, erosion pits were observed on small areas of the cutting tool, resembling the typical signs of cavitation (usually found in much different applications such as pumps and propellers). The discovered wear mechanism denoted as “Cavitation Wear” was used as base for the discussion aimed to deepen the understanding of the conditions close to the sliding interface between the tool and the workpiece. Even though “Cavitation Wear” has been widely reported in hydraulic systems like pumps and water turbines, it is a new phenomenon to be seen on cutting tools while using high-pressure flank cooling.
Alloy 718
Cavitation wear
Coolant boiling
High-pressure coolant
Tungsten carbide
Tool wear mechanism
Författare
Nageswaran Tamil Alagan
Högskolan Väst
Philipp Hoier
Chalmers, Industri- och materialvetenskap, Material och tillverkning
Tomas Beno
Högskolan Väst
Uta Klement
Chalmers, Industri- och materialvetenskap, Material och tillverkning
Anders Wretland
GKN Aerospace Sweden
Wear
0043-1648 (ISSN)
Vol. 452-453 203284Strategiskt forskningssamarbete mellan Chalmers och Högskolan Väst inom Produktionsteknik, (PROSAM) Fas 1&2
Västra Götalandsregionen (RUN612-0208-16), 2016-01-01 -- 2017-12-31.
Västra Götalandsregionen (PROSAM), 2014-01-01 -- 2015-12-31.
Ämneskategorier
Tribologi
Bearbetnings-, yt- och fogningsteknik
Styrkeområden
Produktion
DOI
10.1016/j.wear.2020.203284