PRACTICAL VALIDATION AND HEAT FLOW MODELING OF FSW’ED ALUMINUM ALLOYS

Yıl 2017, Cilt: 19 Sayı: 57, 899 - 907, 01.09.2017

Atilla Savaş Mehmet Turgay Pamuk

Öz

This paper describes the application of the CFD code, Comsol Multiphysics 3.5a, to modeling the three-dimensional heat and metal flow in friction stir welding (FSW) of AA6061-T6 aluminum alloy. The simulation consists of two aluminum plates to be welded, tool and its shoulder. Heat transfer and non-newtonian flow equations were solved simultaneously. The convective heat transfer coefficients underneath the welded plates and the heat given to the system by the tool shoulder were determined by the help of a simple and practical thermal validation. The heat flow along the plates is depicted with changing welding conditions. The flow around the tool pin and shoulder was shown for several different tool rotation rates. This kind of practical validation method helps the welding engineer to simulate nearly all the possible welding conditions without performing expensive experiments. Information obtained from the presented validation and the model can save a lot of engineering hours

Anahtar Kelimeler

FSW, Modeling, Aluminum Alloy

SÜRTÜNME KARIŞTIRMA KAYNAĞI YAPILMIŞ ALÜMİNYUM ALAŞIMLARININ ISI AKIŞININ MODELLEMESİ VE PRATİK DOĞRULAMASI

Öz

Bu makalede AA 6061-T6 alüminyum alaşımının sürtünme karıştırma kaynağının Comsol Multiphysics 3.5a ile yapılan üç boyutlu modellemesi anlatılmıştır. Simülasyon kaynak edilecek iki alüminyum levhasını, kaynak takımını ve kaynak takımının omuz kısmını içermektedir. Isı transferi ve Newtonyen olmayan akış denklemleri aynı anda çözülmüştür. Kaynak edilen plakaların altındaki taşınım ısı transfer katsayısı ve kaynak takımının omuz kısmı tarafından sisteme verilen ısı miktarı basit ve pratik bir ısıl doğrulama yöntemiyle belirlenmiştir. Kaynak edilen plakalar boyunca oluşan ısı akışı değişik kaynak koşulları için gösterilmiştir. Kaynak takımı omzu ve ucu etrafında oluşan metal akışı değişik takım dönme hızları için gösterilmiştir. Bu çeşit bir pratik doğrulama yöntemi kaynak mühendisine neredeyse mümkün olabilecek bütün kaynak koşullarını simüle edebilecek sağlayabilmektedir. Sunumu yapılan doğrulama ve model sayesinde mühendislik zamanından tasarruf yapılabilecektir. imkanı pahalı deneyler yapmadan

Anahtar Kelimeler

Sürtünme Karıştırma Kaynağı, Modelleme, Alüminyum Alaşımı

Kaynakça

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