LASER CUTTING OF TRIANGULAR GEOMETRY INTO ALUMINA TILES: MORPHOLOGICAL CHANGES AND THERMAL STRESS ANALYSIS


Yilbas B. S., Akhtar S. S., Karatas C.

MACHINING SCIENCE AND TECHNOLOGY, cilt.18, sa.3, ss.424-447, 2014 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 18 Sayı: 3
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1080/10910344.2014.925376
  • Dergi Adı: MACHINING SCIENCE AND TECHNOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.424-447
  • Hacettepe Üniversitesi Adresli: Evet

Özet

Laser cutting of triangular geometry into 5-mm-thick alumina tile is carried out. Temperature and stress fields are predicted by using ABAQUS finite element code in line with the experimental conditions. Experiments are carried out to validate the predictions of temperature and the residual stress in the cutting section. Thermocouples are incorporated in temperature measurements while X-ray diffraction technique is accommodated to obtain the residual stress at the kerf surface. The morphological changes in the cutting section are examined by using optical and scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. It is found that temperature and residual stress predictions agree well with their counterparts obtained from the experiments. The optical and SEM micrographs reveal that the cut sections are free from large size defects such as large-scale cracks and sideways burnings. The maximum value of von Mises stress occurs at the mid-thickness of the workpiece due to the formation of high magnitude of thermally induced strain in this region.