FAHRETTİN ÖZTÜRK, Serkan TOROS, SÜLEYMAN KILIÇ

Yüksek Sıcaklıklarda Yüksek Miktarda Yumuşama Eğilimi Gösteren Ti-6Al-4V Alaşımı İçin Yumuşama Modelinin Geliştirilmesi

Ti-6Al-4V (Ti6Al4V veya Ti64) alaşımı, ısıl işlem uygulanabilir ticari titanyum alaşımları içerisinde en çok kullanılan alaşımdır. Fakat bu alaşımın oda sıcaklığında şekillendirilmesi çok kötüdür. Neredeyse karmaşık bir parçanın üretimi imkansızdır. Bu alaşımın yüksek sıcaklıklardaki düzgün uzamadan sonraki deformasyonu oldukça yüksektir. Bu çalışmada, daha önce aluminyum-magnezyum alaşımları için geliştirilmiş olan Yumuşama Modeli (YM) iyileştirilerek yüksek sıcaklıklarda yüksek miktarda yumuşama eğilimi gösteren Ti-6Al-4V alaşımının akma eğrisinin tahmin edilebilme kabiliyeti arttırılmıştır. İyileştirilen model Geliştirilmiş Yumuşama Modeli (GYM) olarak adlandırılmıştır. Sonuçlar, Geliştirilmiş Yumuşama Modeli'nin Ti-6Al-4V alaşımı için mevcut Yumuşama Modeli'ne göre daha doğru tahmin yaptığını göstermiştir

Improvement ofSoftening Model for Ti-6Al-4VAlloy Havinga High Softening Tendency at Elevated Temperatures

Ti-6Al-4V (Ti6Al4V or Ti64) is the most commercially used heat treatable alloy in titanium alloys. However, room temperature (RT) formability of this alloy is very poor and it is almost impossible to produce complex shaped parts. It has significant post uniform elongation at high temperature deformations. In this study, a previously proposed softening model (SM) for aluminum-magnesium (Al-Mg) alloys was improved in order to increase flow curve prediction capability for Ti-6Al-4V alloy having a high softening tendency at elevated temperatures. The improved model was called as Improved Softening Model (ISM). Results indicate that the ISM has more accurate prediction than the SM for Ti-6Al-4V alloy

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