Nikel esaslı süper alaşımın (Nimonic 80A) malzeme yapısal denklem parametrelerinin belirlenmesi ve uygulanabilirliğinin araştırılması
Küçük Resim Yok
Tarih
2018
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Karabük Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu çalışma, Nimonic 80A nikel esaslı süper alaşımın malzeme modelini literatüre kazandırmayı amaçlamakta ve üç aşamadan oluşmaktadır. İlk aşamada Nimonic 80A süper alaşımın Johnson-Cook malzeme modelinin belirlenmesi amaçlanmıştır. Sonlu elemanlar yöntemine dayalı analiz programlarında, belirlenen iş parçası malzemesine işleme simülasyonları yapabilmek için Johnson-Cook malzeme modeli gereklidir. Bu bağlamda, malzemeye ilk olarak oda sıcaklığında 10-3, 10-2 ve 10-1 s-1 gerinim hızlarında yarı-statik testler uygulanmıştır. Ardından Split Hopkinson Basınç Çubuğu Test cihazı yardımıyla oda sıcaklığında 370, 720 ve 954 s-1 gerinim hızlarında dinamik testler gerçekleştirilmiştir. Son olarak en düşük gerinim hızı olan 10-3 s-1 hızında 300, 600 ve 900 °C sıcaklıklarda yüksek sıcaklık testleri uygulanmıştır. Bu testlerden elde edilen veriler yardımıyla Nimonic 80A malzemesine ait Johnson-Cook parametreleri belirlenmiştir. İkinci aşamada, kaplamalı karbür kesici takımlarla Nimonic 80A malzemesine ait tornalama deneyleri gerçekleştirilmiştir. Son aşamada, belirlenen malzeme modeli, sonlu elemanlar metodu tabanlı simulasyon programına yüklenip tornalama deneyleri, tornalama simulasyonları ile kıyaslanmış ve aralarında ortalama %6,45 fark tespit edilmiştir. Bu sayede, yeni oluşturulan malzeme modelinin doğruluğu ve uygulanabilirliği ipsatlanmış olup, ulusal ve uluslararası literatüre yeni veriler kazandırılmıştır.
This study aims to provide the material model of Nimonic 80A nickel based superalloy to the literatüre and it consists of three steps. In the first step, identification of Johnson-Cook material model for Nimonic 80A super alloy was determined. The Johnson-Cook material model is required in the analysis programs based on the finite element method in order to simulate the machining of the specified workpiece material. In this context, the material was firstly subjected to quasi-static tests at 10-3, 10-2 and 10-1 s-1 strain rates at room temperature. Dynamic tests were then performed at room temperature with 370, 720 and 954 s-1 strain rates using the Split Hopkinson Pressure Bar. Finally, high temperature tests were applied at 300, 600 and 900 ° C at the lowest strain rate of 10-3 s-1. The Johnson-Cook parameters of Nimonic 80A material were determined with the help of the data obtained from these tests. In the second step, turning process of Nimonic 80A material were carried out with coated carbide cutting tools. At the last stage, the determined material model was adapted to the simulation software based on finite element method in order to compare turning experiments and turning simulations. The mean deviation of 6,45% was identified between them. Thus, the accuracy and applicability of the newly created material model was approved and new data were gained to national and international literature.
This study aims to provide the material model of Nimonic 80A nickel based superalloy to the literatüre and it consists of three steps. In the first step, identification of Johnson-Cook material model for Nimonic 80A super alloy was determined. The Johnson-Cook material model is required in the analysis programs based on the finite element method in order to simulate the machining of the specified workpiece material. In this context, the material was firstly subjected to quasi-static tests at 10-3, 10-2 and 10-1 s-1 strain rates at room temperature. Dynamic tests were then performed at room temperature with 370, 720 and 954 s-1 strain rates using the Split Hopkinson Pressure Bar. Finally, high temperature tests were applied at 300, 600 and 900 ° C at the lowest strain rate of 10-3 s-1. The Johnson-Cook parameters of Nimonic 80A material were determined with the help of the data obtained from these tests. In the second step, turning process of Nimonic 80A material were carried out with coated carbide cutting tools. At the last stage, the determined material model was adapted to the simulation software based on finite element method in order to compare turning experiments and turning simulations. The mean deviation of 6,45% was identified between them. Thus, the accuracy and applicability of the newly created material model was approved and new data were gained to national and international literature.
Açıklama
Fen Bilimleri Enstitüsü, Makine Mühendisliği Ana Bilim Dalı
Anahtar Kelimeler
Makine Mühendisliği, Mechanical Engineering
