A thermo-mechanical model of drill margin-borehole surface interface contact conditions in dry drilling of thick CFRP laminates
Yükleniyor...
Dosyalar
Tarih
2020-04-23
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Ltd
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Dry drilling of thick carbon fiber reinforced polymer (CFRP) laminates requires careful selection of process parameters in order to obtain acceptable borehole surface quality. Complex contact conditions between the drill margin and the borehole surface determine the integrity of the borehole surface depending on the process parameters and temperature-dependent viscoelastic material properties. Temperature rise during dry drilling reduces the elastic modulus of the CFRP and causes thermal expansion of the drill, resulting in considerable contact length at the drill margin and borehole surface interface. Manufacturers need a better understanding of the interaction among contact pressure, sliding velocity, temperature at the interface, and temperature-dependent material properties to develop predictive models for drilling CFRPs. To examine this complex interaction, this study develops a novel, hybrid model that combines a time-based analytical modeling of drilling process with a finite element-based modeling of temperature rise. Drilling experiments were performed in which thrust force, torque, and temperature were measured as a function of feed, and these measurements were used to identify unknown hybrid model parameters. The results revealed that a significant change in friction conditions occurs when increased temperatures at the margin and borehole surface interface approach and exceed the glass transition temperature of the CFRP laminate at a large feed rate. These findings show the benefit of increasing feed during dry drilling, which is nonetheless limited by the temperature-dependent material properties of the work material.
Açıklama
Anahtar Kelimeler
Beams and girders, Boreholes, Carbon fiber reinforced plastics, Carbon fiber reinforced polymer, Composite structures, Drilling, Drills, Fiber reinforced polymers, Friction conditions, Glass transition, Increased temperature, Infill drilling, Selection of process parameters, Temperature dependent, Temperature-dependent material properties, Thermal expansion, Thermomechanical model, Visco-elastic material, Viscoelasticity
Kaynak
International Journal of Machine Tools and Manufacture
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
154
Sayı
Künye
Karpat, Y., Karagüzel, U. & Bahtiyar, O. (2020). A thermo-mechanical model of drill margin-borehole surface interface contact conditions in dry drilling of thick CFRP laminates. International Journal of Machine Tools and Manufacture, 154, 1-15. doi:10.1016/j.ijmachtools.2020.103565
