High pressure coolant on hard turning processes

• Main Author: Seow, Zhi Xian
• Other Authors: Yeo Swee Hock
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Materials::Mechanical strength of materials
• Online Access: http://hdl.handle.net/10356/78816
• Institution: Nanyang Technological University

Inconel 625 was machined with a PVD coated (Ti,Al)N+(Al,Cr)2O3 carbide tool at speeds up to 60 m/min using varied coolant pressures, up to 7 MPa with and without a tail stock. The cutting forces, surface roughness (Ra) and tool wear were recorded and analysed. The results show that machining Inconel 625 with a high pressure coolant supply increases the cutting force components compared to dry machining. This can be attributed to the ability of the nickel-based alloy to strain harden under thermo-mechanical loading conditions. Vibrations during the machining process can result in up to 30% reduction in surface quality. Cutting forces generated when Inconel 625 was machined with high pressure, with a tail stock, are lower than when machined without. The tools machined with high pressure coolant has a higher failure rate at a higher coolant pressure. The higher the feed, the greater the observed tool wear. Built up edge was the dominant kind of tool wear in the dry machining operation. This could be due to the lack of lubricity provided by the coolant.