Performance analysis of untreated, cryo-treated and coated carbide inserts during dry turning of Incoloy 825: A comparative study

Incoloy 825, known for its impressive corrosion resistance, exceptional capability to survive in acidic and chloride environment and mechanical strength, finds extensive application in aerospace, chemical, nuclear, marine and various other industries. Nevertheless, the wide range of application of dry turning in machining Incoloy 825 presents significant challenges, such as toughness, high heat resistance, low thermal conductivity and creep resistance. These issues make the machining of Incoloy 825 a formidable task. In the present investigation, analysing the suitability of advanced cutting tools in dry turning environment by comparison of the result of the uncoated carbide tool, cryo-treated carbide tool and coated carbide tool for various testing parameters such as surface temperature, surface roughness, tool wear and the chip reduction coefficient. A round bar of Incoloy having a diameter of 51 mm and a length of 320 mm was turned at three distinct cutting speeds viz. 51, 76 and 107 m/minute, for cutting intervals of 30, 60, 90 and 120 seconds, respectively. However, the values of the other two machining variables were kept as constant, that is, feed rate = 0.1 mm/rev and depth of cut = 0.5 mm throughout the experiment. The result suggests that the coated and cryo-treated inserts perform better at all predefined cutting speeds as compared to the uncoated counterpart. Coated tool was found to be most favourable as it demonstrated superior results for all the testing parameters except tool wear.