Self-Excited Vibrations in Turning: Efforts Torsor and Average Friction Coefficient Analysis

TL;DR

This paper investigates self-excited vibrations in turning processes using a six-component dynamometer to measure cutting forces, analyzing efforts, torsor, and friction coefficients under different cutting conditions.

Contribution

It introduces an experimental approach to analyze efforts and friction coefficients during self-excited vibrations in turning, with detailed measurements and innovative insights.

Findings

Friction coefficient of swivelling increases with feed rate.

Friction coefficient of bearing decreases with feed rate.

Evolution of average friction coefficient varies with depth of cut and feed rate.

Abstract

An experimental device in turning including, in particular, a six-component dynamometer is exploited to measure the complete torque of cutting forces in a case of self-excited vibrations. For the tests, the tool used is type TNMA 16 04 12 carbide not covered (nuance carbide-SUMITIMO ELECTRIC), without chip breeze. The machined material is an alloy of chrome molybdenum type 42 CrMo24. The test-tubes are cylindrical with a diameter of 120 mm and a length of 30 mm. The effort of analysis relates to the moments. In particular, to the tool tip point, when feed rate increases the friction coefficient of swivelling is increasing while that of bearing is decreasing. Innovative remarks on the evolution of the average friction coefficient for various depths of cut and feed rate are presented