Fe elementindekα→γ→δ Katı-Katı Faz Geçişlerinin Moleküler Dinamik Benzetimi ile İncelenmesi

Fe elementinin faz diyagramı incelendiğinde erime sıcaklığının altında farklı sıcaklıklarda farklı kristal yapılara sahip olduğu görülmektedir. Bu çalışmada 4000 atomdan oluşan Fe model sisteminde farklı sıcaklıklarda meydana gelen katı-katı faz dönüşümleri moleküler dinamik benzetim yöntemi kullanılarak incelenmeye çalışıldı. Çok cisim etkileşmelerini içeren Gömülmüş Atom Metodu(GAM) atomlar arasındaki etkileşmeleri hesaplamak için kullanıldı. Fe elementi için erime sıcaklığının altında oluşan α, γ ve δ fazları ve bu fazlar için dönüşüm sıcaklıkları belirlenerek sonuçlar deneysel değerlerle karşılaştırıldı. Model sistemin yapısal analizlerinde radyal dağılım fonksiyonu, termodinamik niceliklerde değişimler ve Ackland-Jones analiz yöntemi kullanıldı. Erime sıcaklığına kadar olan faz geçişlerinin gözlenmesi, hesaplamalarda kullanılan potansiyel fonksiyonunun Fe’nin sistemin modellenmesinde başarılı bir şekilde kullanılabileceğini göstermektedir.

The Investigation with Molecular Dynamic Simulation of α→γ→δ Solid-Solid Phase Transformation in Fe

When the phase diagram of the element Fe is examined, it is seen that it has different crystal structures at different temperatures below its melting temperature. In this study, the solid-solid phase transformations occurring at different temperatures in the Fe model system consisting of 4000 atoms were investigated using molecular dynamic simulation method. The Embedded Atom Method(EAM), which includes many body interactions, was used to calculate interactions between atoms. For the element Fe, the α, γ and δ phases formed below the melting temperature and the transformation temperatures for these phases were determined and the results were compared with the experimental values. Radial distribution function, changes in thermodynamic quantities and Ackland-Jones analysis method were used in the structural analysis of the model system.

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