Geri Dön

Mechanics and dynamics of milling thin-walled structures

Başlık çevirisi mevcut değil.

  1. Tez No: 400702
  2. Yazar: ERHAN BUDAK
  3. Danışmanlar: DR. YUSUF ALTINTAŞ
  4. Tez Türü: Doktora
  5. Konular: Makine Mühendisliği, Mechanical Engineering
  6. Anahtar Kelimeler: Belirtilmemiş.
  7. Yıl: 1994
  8. Dil: İngilizce
  9. Üniversite: The University of British Columbia
  10. Enstitü: Yurtdışı Enstitü
  11. Ana Bilim Dalı: Makine Mühendisliği Ana Bilim Dalı
  12. Bilim Dalı: Belirtilmemiş.
  13. Sayfa Sayısı: 286

Özet

Özet yok.

Özet (Çeviri)

Peripheral milling of flexible components is a commonly used operation in the aerospace mdustrj'. Aircraft wings, fuselage sections, jet engine compressors, turbine blades and a variety of mechanical components have flexible webs which must be finish machined using long slender end mills. Peripheral milling of very flexible plate structures made of titanium alloys is one of the most complex operations in the aerospace industry and it is investigated in this thesis. Flexible plates and cutters deflect statically and dynamically due to periodically varying milling forces and self excited chatter vibrations. Static deflections of the plate and cutter cause dimensional form errors, whereas forced and chatter vibrations result in poor surface quality and chipping of the cutting edges. In this thesis, a comprehensive model of the peripheral milling of very flexible cantilever plates is presented. The plate and cutter structures are modeled by 8 node finite elements and an elastic beam, respectively. The cutting forces are shown to be very dependent on the magnitude of the plate and cutter deformations which are irregular along the helical end mill-plate contact. The interaction between the milling process and cutter-plate structures is modeled, and the milling forces, structural deformations and dimensional form errors left on the finish surface are accurately predicted by the simulation system developed in this study. A strategy, which constrains the maximum dimensional form errors caused by static deformations of plate and cutter by scheduling the feed along the tool path, is developed. The variation of the plate thickness due to machining and the partial disengagement of the plate and cutter due to excessive static deflections are considered in the model. The simulation system is proven in numerous peripheral milling experiments with both rigid blocks and very flexible cantilevered plates.The self excited vibrations observed during peripheral milling of very flexible structures with multi-degree of freedom dynamics is investigated. A novel analytical model of milling stability is developed. The stability model requires structural transfer functions of plate and cutter, milling force coefficients and helical end mill geometry. Chatter vibration free cutting speeds, axial and radial depths of cut, i.e. stability lobes, are predicted analytically without resorting to computationally expensive time domain simulations. The analytical chatter stability model is verified in various peripheral milling experiments, including the machining of plates. The cutting force and chatter stability models developed in this thesis can be used to improve the productivity of peripheral milling of thin webs by enabling simulation and process planning prior to production.

Benzer Tezler

  1. Modeling milling of thin-walled parts considering dynamic structure-process interactions

    İnce cidarlı parçaların frezelenmesi işleminin dinamik yapı-süreç etkileşimlerinin hesaba katılarak modellenmesi

    SALTUK YILDIZ

    Yüksek Lisans

    İngilizce

    İngilizce

    2022

    Makine MühendisliğiSabancı Üniversitesi

    Üretim Mühendisliği Ana Bilim Dalı

    DOÇ. DR. LÜTFİ TANER TUNÇ

    PROF. DR. ERHAN BUDAK

  2. Mechanics, dynamics, and stability of orthogonal turn-milling operation

    Dik frezeyle tornalama işleminin mekaniği, dinamiği, ve kararlılığı

    KAVEH RAHIMZADEH BERENJI

    Doktora

    İngilizce

    İngilizce

    2022

    Makine MühendisliğiSabancı Üniversitesi

    Üretim Mühendisliği Ana Bilim Dalı

    PROF. DR. ERHAN BUDAK

  3. Design and optimization of end mills with special geometries for high productivity and their use in different applications

    Özel geometrili freze takımlarının yüksek verimlilik içintasarımı, optimizasyonu ve farklı uygulamalarda kullanımı

    FARAZ TEHRANIZADEH

    Doktora

    İngilizce

    İngilizce

    2021

    Makine MühendisliğiSabancı Üniversitesi

    Üretim Mühendisliği Ana Bilim Dalı

    PROF. DR. ERHAN BUDAK

  4. Cam elyaf takviyeli SMC kompozitlerin işlenebilirlik ve vidalı birleştirme yeteneklerinin incelenmesi

    The investigation of machinability and threaded joint ability of SMC glass fiber reinforced composites

    HASAN GÜNDOĞDU

    Yüksek Lisans

    Türkçe

    Türkçe

    2018

    Makine MühendisliğiNecmettin Erbakan Üniversitesi

    Makine Mühendisliği Ana Bilim Dalı

    YRD. DOÇ. DR. AHMET CAN

  5. Karbon fiber takviyeli kompozitlerin işlenebilirliği ve vidalı birleştirme yeteneklerinin incelenmesi

    The investigation of machinability and threaded joint capability of carbon fiber reinforced composites

    ÖZGÜR BİÇER

    Yüksek Lisans

    Türkçe

    Türkçe

    2017

    Makine MühendisliğiNecmettin Erbakan Üniversitesi

    Makine Mühendisliği Ana Bilim Dalı

    YRD. DOÇ. DR. AHMET CAN