9 research outputs found
Depth Profiles of Residual Stresses in Inconel 718Machined with Uncoated and Coated Tools
567-573Inconel 718 is one of the super-alloy materials, belonging to nickel-chromium alloy family, which has major applications
in aerospace sector such as engine parts and turbine components. Durability of these components during engineering
performance is affected by residual stresses induced in them in the course of their manufacturing processes. The concept of
the present paper is to provide an insight view of induced residual stresses in Inconel 718 work piece, when machined with
coated (TiN) and uncoated tools at optimum conditions. For this purpose, turning experiments have been conducted on
IN718 material through statistical approach using L9 orthogonal array. Taguchi optimization method is exercised with the
emphasis on minimizing the cutting forces resulted during machining. The residual stresses generated in the work piece at
the optimum conditions employed for both the tools have been evaluated using XRD method. Conditions such as cutting
speed of 60 m/min, feed at 0.068 mm/rev and depth-of-cut of 0.10 mm have been optimized for achieving minimum cutting
forces during machining of IN 718 using both coated and uncoated tools. However, tensile stresses on the initial surface
layer and compressive stresses in the sub-surface layers are found higher in the work piece material machined with uncoated
tool. Surface roughness and temperature developed on the surface of the machined bar are higher in case of uncoated tool
than those with coated tool