Mikroyapı Gelişiminin Temellerini Gerçek Zamanlı Olarak İncelemek için Mikroskop ve Katılaştırma Ekipmanı Tasarımı

Öz

Katılaşma mikroyapısı, döküm, eklemeli imalat ve kaynak yoluyla üretilen malzemelerde malzeme özelliklerini belirleyen en önemli parametrelerden biridir. Mikroyapıyı kontrol etmek ve optimize etmek için öncelikle mikroyapı evrim dinamiklerinin anlaşılması gerekir. Post-mortem çalışmalarla mikroyapıyı anlamak için birçok girişimde bulunulmasına rağmen, büyüme hızı gibi mikroyapıyı belirleyen bir parametre değiştiğinde ne olacağını anlamak için gerçek zamanlı araştırmalar gereklidir. Gerçek zamanlı inceleme, özellikle hız, kompozisyon, sıcaklık gradyanı vb. gibi katılaşma parametrelerinin işlem sırasında değiştiği döküm, katmanlı imalat ve kaynak gibi endüstriyel uygulamalarda katılaşma mikroyapısının ve dolayısıyla malzeme özelliklerinin belirlenmesi için çok önemlidir. Bu çalışmada, katılaşma dinamiklerini ve mikroyapı gelişimini gerçek zamanlı olarak incelemek amacıyla özel bir mikroskop ve katılaşma düzenekleri tasarlanmış ve imal edilmiştir. Yönlü katılaşma deney düzenekleri ile birlikte mikroskopi sisteminin detayları sunulmaktadır. Sıcaklık gradyanı ölçümleri, tipik kontrol parametreleri ve mikroyapılar dahil olmak üzere bu tekniğin örnek çıktıları raporlanmıştır. Bu özel üretim ekipmanın, metalik sistemlerde dahi katılaşma dinamiklerini ve mikroyapı gelişimini üç boyutlu olarak anlamanın ve böylelikle malzeme özelliklerini belirlemenin yolunu açtığı gösterilmiştir.

Anahtar Kelimeler

• Katılaşma
• Mikroyapı Evrimi
• Mikroskopi
• Fiziksel Metalurji
• Tek Yönlü Katılaşma

Microscope and Solidification Equipment Design to Study in Real Time the Fundamentals of Microstructure Evolution

Öz

Solidification microstructure is the decisive parameter in determination of all kinds of properties in materials produced by casting, additive manufacturing, and welding. In order to control and optimize the microstructure, first, the microstructure evolution dynamics has to be understood. Although there have been many attempts to understand microstructure with post-mortem studies, real-time investigation is necessary to apprehend what happens when a microstructure decisive parameter such as growth velocity changes. Real-time investigation is especially important for determination of microstructure in industrial applications such as casting, additive manufacturing, and welding, where the solidification parameters such as velocity, composition, temperature gradient etc. change during the process. In this work, in order to investigate solidification dynamics and microstructure evolution in real time, a special microscope and solidification setups were designed, and get manufactured. The details of the microscopy system are given along with the directional solidification setups. Example outputs of this technique including temperature gradient measurements, typical setting parameters, and microstructures are reported. It is shown that this unique equipment opens the way to understand the solidification dynamics and microstructure evolution even in metallic systems in three dimensions, and hence the material properties.

Anahtar Kelimeler

• Solidification
• Microstructure Evolution
• Microscopy
• Physical Metallurgy
• Directional Solidification

Kaynakça

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