Predicting the Effects of Rake Angle, Cutting Speed and Feed Rate on Chip Morphology in Hard Turning

Abstract

This paper proposes a thermo-mechanical orthogonal cutting finite element model (FEM) to investigate the variation of chip morphology from continuous chip to small and large saw-tooth chip. The corresponding experiments of hard turning AISI 52100 steel are conducted to validate the proposed FE model. Three one-factor simulation experiments are conducted to determine the evolution of chip morphology along feed rate, rake angle and cutting speed respectively. The chip morphology evolution is described by the variations of dimensional values, saw-tooth degree and chip segmental frequency. The research suggests that chip morphology transit from continuous to sawtooth chip with increasing the feed rate and cutting speed, and changing a positive rake angle to a negative rake angle. There exists a critical cutting speed at which the chip morphology transfers from continuous to saw-tooth chips. The saw-tooth chip segmental frequency decreases as the feed rate and negative rake angle value increase, but increases almost linearly with the cutting speed. The larger negative rake angle, the larger feed rate and high cutting speed dominate the sawtooth chip morphology while positive rake angle, small feed rate and low cutting speed determine continuous chip morphology.

Experimental investigation of the effect of machinability on surface quality and vibration in hard turning of hardened AISI 4140 steels using ceramic cutting tools

“…Optimum surface qualities were seen in the parameters with high cutting speeds and low feed rate. [1][2][3][20][21][22][23][24][25][26][27][28][29][30][31] Ra and Rz values were obtained lower than CHT sample in the T sample where the second tempering process was applied. The machinability has improved due to the increase in toughness values by decreasing the hardness in the samples with the second tempering process.…”

“…15 Elsheikh et al (2019) investigated the effects of cutting parameters on the surface residual stresses of the AISI 1035 alloy steel in turning process. 16 In the literature studies, many researchers explain that chip morphology is influenced by cutting parameters like cutting speed, 26 feed rate 27 and sample hardness. 28 In this experimental study, effect of machinability on surface quality and vibration were analyzed in hard turning of hardened AISI 4140 steel materials.…”