Al-Si alaşımlarında silisyum miktarının döküm parça-kalıp aryüzey ısı transfer katsayısı üzerine etkisi

Bu çalışmanın amacı katılaşma süresince su soğutmalı bakır soğutucu üzerinde tek yönlü dikey olarak katılaşan Al-Si alaşımlarında silisyum içeriğinin arayüzey ısı transferi katsayısına etkisini incelemektir. Arayüzey ısı transfer katsayısı silisyum içeriğine bağlı olarak, Sonlu Farklar Metoduna dayalı FORTRAN programı ile belirlenmiştir. Sonuç olarak; arayüzey ısı transfer katsayısı silisyum içeriğinin azalması ile artmıştır, maksimum arayüzey ısı transfer katsayısı değerleri; %7Si’de 8900 W/m2K, %5Si’de 14600 W/m2K ve %3Si’de 19100 W/m2K olarak elde edilmiştir.

Effect of silicon content in Al-Si alloys on heat transfer coefficient at casting-mold interface

The objective of the present work was to investigate the effect of silicon content on the interfacial heat transfer coefficient (IHTC) for vertically upward unidirectional solidification of Al-Si casting on water cooled cupper chills during solidification. The interfacial heat transfer coefficient measured as a function of different silicon content was determined by using finite difference method solving FORTRAN language. The obtained results; the heat transfer coefficients increases as silicon content decreases, the maximum heat transfer coefficient values were obtained; 8900 W/m2K with %7, 14600 W/m2K with %5 and 19100 W/m2K with %3 silicon content.

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