High-Speed Machining Process of Titanium Alloy: A Comprehensive Finite Element Modeling

Öz

This study comprehensively deals with a two-dimensional finite element (FE) modeling and simulation for chip formation process of titanium alloy. The basic parameters, such as chip shape, workpiece surface, equivalent stress, plastic strain and cutting force, are analyzed to study the impact of a variety of rake angles during high-speed machining. The chip shapes vary with the tool-rake angle. During the serrated chip formation, the primary deformation region exhibits substantially higher stress than secondary region. Also, the higher strains are occurred at the chip roots. The fluctuation of the cutting force caused by the serrated chip is more prominent than that obtained during the continuous chip formation, and the force varies periodically. The results also show that an increase in the positive direction of rake angle causes a decrease in cutting force and a smoother workpiece surface.

Anahtar Kelimeler

• Chip formation
• FE modeling
• high-speed machining

Titanyum Alaşımının Yüksek-Hızlı İşleme Süreci: Kapsamlı Sonlu Eleman Modelleme

Öz

Bu çalışma, titanyum alaşımının talaş oluşumu süreci için iki boyutlu sonlu eleman (SE) modelleme ve benzetimini kapsamlı bir şekilde ele almaktadır. Yüksek hızlı işleme sırasında çeşitli talaş açılarının etkisini incelemek için talaş şekli, iş parçası yüzeyi, eşdeğer gerilme, plastik gerinim ve kesme kuvveti gibi temel parametreler analiz edilmiştir. Talaş şekilleri, takım talaş açısıyla değişmektedir. Testere ağızlı talaş oluşumu sırasında, birincil deformasyon bölgesi, ikincil bölgeden önemli ölçüde daha yüksek gerilme sergilemektedir. Ayrıca, yüksek gerinimler talaş köklerinde meydana gelmiştir. Testere ağızlı talaşın neden olduğu kesme kuvveti dalgalanması, sürekli talaş oluşumu sırasında elde edilenden daha belirgindir ve kuvvet periyodik olarak değişmektedir. Sonuçlar, talaş açısının pozitif yöndeki artışının kesme kuvvetinde azalmaya ve daha pürüzsüz bir iş parçası yüzeyine yol açtığını da göstermektedir.

Anahtar Kelimeler

• Talaş oluşumu
• SE modelleme
• yüksek-hızlı işletme
• titanyum

Kaynakça

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