Prediction Of Surface Quality Using Chip Morphology With Nodal Temperature Signatures In Hard Turning Of AISI D3 Steel

Abstract

Though there are many works on hard turning using coated carbide and ceramic cutting tools, there is hardly little work using hybrid ceramic matrix cutting tool, during turning of AISI D3 steel, whose applications are many. Therefore, the present experiment focused on the mixed ceramic matrix (Al2O3 + TiCN) tool for the turning of heat treated cold work AISI D3 tool steel and the effect of cutting parameters within the cutting speed range of (80 - 320 m/min), feed rate in the range of (0.04 - 0.08 mm/rev) and depth of cut within (0.1 - 0.9 mm) upon surface roughness, cutting forces and nodal temperature using Taguchi design of experiment. The chip morphology i.e., machined chip colour, shape, and thickness for different cutting parameters have been studied experimentally in detail and concluded that during cutting parameters (cutting speed 320m/min, feed rate 0.05mm/rev, depth of cut 0.1mm) the machined surface integrity was found significant (Ra=0.48 µm) due to higher cutting speed & feed rate with corresponding decrease in depth of cut. Due to increase in temperature the colour of chip was found golden at the cutting zone with ribbon (saw tooth) type shape. The surface roughness was increased to (Ra=4.53 µm) at cutting parameters (cutting speed 140m/min, feed 0.07mm/rev and depth of cut 0.9mm) due to increase in feed and depth of cut and the colour of chip were found to be metallic with ribbon (saw tooth) type shape. Thus, it was found that the chip colour and shape is strongly related to indicate tool condition as well as surface integrity. The optimum cutting parameters were cutting speed of 80 m/min with feed rate of 0.06mm/rev and depth of cut 0.5 mm to minimise the value of surface roughness when nodal temperature was 71.1°C. The acquired nodal temperature has found to be strongly correlated to machined surface quality in terms of roughness. However, the chip morphology along with nodal temperature may be used to improve predictability of surface integrity in a better way.