Investigation of the effect of Chip Slenderness Ratio and Cutting Tool Approach Angle on Vibration Amplitudes and Chip Morphology

Abstract

Machinability, especially turning process, is a significant manufacturing method, but the vibrations, arisen from the natural mechanism of the process, make difficulties. Unnumbered parameters influence the process outcomes such as surface roughness, chip morphology, and vibration amplitudes. In the present paper, the effect of tool approach angle and chip slenderness ratio (CSR) on the vibration amplitudes, StDev in vibrations, and chip morphology were investigated. For this purpose, 15^o, 30^o, and 45^o approach angles, 1, 3, 5, 10, and 15 CSR also depending on CSR values 0,1 mm/rev, 0,15 mm/rev, 0,45 mm/rev, and 0,5 mm/rev feed rates, 0,5 mm, 1 mm, 1,5 mm, and 2,25 mm cutting depths were selected. It was investigated that according to both vibration amplitudes and chip morphology criterion, the most appropriate cutting tool approach angle was 30^o, and CSR values were 10 and 15. Besides, as the tool approach angle progress, the vibration amplitudes in the X (cutting depth) direction were deteriorated, but at small CSR values, they were increased. The optimum feed rates were to be 0,1 mm/rev and 0,15 mm/rev, but the influence of the cutting depth showed differences depending on the values of the selected feed rates. Surface quality was improved at 30^o and 45^o approach angles, 0,1mm/rev and 0,15 mm/rev feed rates and10 and 15 CSR values. The chips in lamellas form, without severe deformation cracks and serration formation were observed at 30^o approach angle, 0,1 mm/rev and 0,15 mm/rev feed rates also at 10 and 15 CSR values.

Keywords

• Turning,Chip slenderness ratio (CSR),Tool approach angle,Chip morphology,Machinability,Surface roughness

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