Nickel-based superalloy Inconel 718 is widely used in the aerospace industry, turbines and high-temperature applications because of its superior properties at elevated temperatures. Its critical thermal behavior during machining necessitates a detailed investigation of thermal effects. The purpose of this study is to present a novel approach to subsurface temperature measurement in the difficult-to-machine material Inconel 718, aimed at identifying critical thermal conditions during grinding.
The embedded thermocouple method was used for temperature measurement in this investigation, owing to its low cost, durability and reliable performance in capturing critical temperature values. Dry and wet environments have been implemented to study the thermal behavior of the material and its correlation with process parameters. To control thermal damage and ensure good surface quality in grinding, proper selection of machining parameters is essential.
By comparing the dry and wet grinding data, the minimum grinding temperature is obtained at depth of cut of 5 µm, wheel speed of 628 m/min and table speed of 6,000 mm/min. Statistical analysis was conducted to determine the significance of process variables, revealing that depth of cut is the most influential parameter, followed by wheel speed and table speed. The maximum mean grinding temperature recorded was 98°C under wet grinding and 186°C under dry grinding conditions.
The experimental findings were validated using a statistical regression model, which showed strong agreement with the measured data. Wet grinding consistently resulted in lower temperatures compared to dry grinding, contributing to improved surface quality and reduced thermal damage.
