The effect of cutting tool material on chatter vibrations and statistical optimization in turning operations

Gok F., ORAK S., SOFUOĞLU M. A.

SOFT COMPUTING, cilt.24, sa.22, ss.17319-17331, 2020 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 24 Sayı: 22
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1007/s00500-020-05022-3
  • Dergi Adı: SOFT COMPUTING
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Applied Science & Technology Source, Compendex, Computer & Applied Sciences, INSPEC, zbMATH
  • Sayfa Sayıları: ss.17319-17331
  • Anahtar Kelimeler: Chatter vibration, Stable cutting depths, Statistical optimization, Ceramic inserts, MACHINING PARAMETERS, STABILITY, PITCH, PREDICTION, SELECTION, DESIGN, ALGORITHM, FORCE
  • Eskişehir Osmangazi Üniversitesi Adresli: Evet

Özet

Machine tool vibrations consist of a self-stimulating mechanism during chip removal by machining operations. The system, which is a structural mode of the tool/workpiece, is initially stimulated by force. In turning operations, a wavy surface is formed on the workpiece because of both the previous revolution and structural vibrations. The maximum chip thickness may exponentially increase due to the phase shift between two consecutive waves, while the system oscillates at a chatter frequency very close to its structural mode. Variable growth in chip thickness increases vibrations, cutting forces and tool wear and causes a wavy surface. The purpose of the study is to compare different cutting tool inserts in terms of stable cutting depths. First, an experimental study was carried out and the stable cutting depths without chatter vibrations were determined in turning operations using various materials (AISI-1010, AISI-1050, Al-7075). Alumina inserts (Al2O3) were used in the study. Stable cutting depths were compared with the literature study that was performed using titanium carbide (TiC) inserts. A paired t test was used for the comparison. After the experimental study, a statistical/optimization study was performed to optimize stable cutting depths. It was observed that the chatter frequency was generally higher than the natural frequency of the cutting tool. Also, it was observed that the decrease in the number of revolutions, tool overhang lengths and yield strength of workpiece results in higher stable cutting depths. When the number of revolution is 125 rpm, the overhang length is 70 mm, and the yield strength is 124 MPa, the stable cutting depths maximize. In addition, stable cutting depths were higher when using Al2O3 cutting tool inserts and chatter vibrations were prevented. There was a significant difference between the two inserts (p < 0.05). It was found that the Al2O3 cutting tool inserts had better performances than TiC cutting inserts for the hard materials.