Politeknik Dergisi 2147-9429 Gazi Üniversitesi 10.2339/politeknik.746862 Engineering Mühendislik Alüminyum Alaşımlarının Ahtapot Akışkanlık Testi ile Karakterizasyonu Characterisation of Aluminum Alloys by Octopus Fluidity Test https://orcid.org/0000-0001-6774-1258 Erzi Eray İSTANBUL ÜNİVERSİTESİ - CERRAHPAŞA https://orcid.org/0000-0001-9591-6430 Yüksel Çağlar ATATURK UNIVERSITY https://orcid.org/0000-0003-2087-420X Gursoy Ozen University of Padova https://orcid.org/0000-0002-8255-5987 Çolak Murat BAYBURT UNIVERSITY https://orcid.org/0000-0001-9550-6933 Dıspınar Derya İSTANBUL TEKNİK ÜNİVERSİTESİ 02 29 2024 27 1 21 25 06 03 2020 10 23 2020 Copyright © 1998, Politeknik Dergisi 1998 Politeknik Dergisi

Alüminyum ve alaşımları hafiflik ve yüksek mukavemet oranlarından dolayı taşımacılık sektöründe en yaygın şekilde kullanılan alaşımlardır. Bu alaşımın neden tercih edildiğinin sebebini yüksek korozyon direnci pekiştirmektedir. Mukavemet değerlerinin arzu edilen seviyelere yükseltmek için alüminyum ve alaşımları, Ti ile tane inceltme, Mg ve Cu ile çökelme sertleşmesi ve Sr ile içyapısal değişimlere tabi tutulurlar. Bu çalışmada Al-Cu alaşımına Ag ilavesi, Al-Si alaşımlarına Sr ilavesi ile kalıp dolum kabiliyeti arasındaki ilişki araştırılmıştır. Geleneksel sarmal (spiral) testlere ilave olarak yeni geliştirilen ahtapot tasarımı olarak isimlendirilen 8-kollu kalıp akışkanlığı karakterize etmek için kullanılmıştır. Al-Cu alaşımına (201) Ag ilavesi spiral akışkanlığa hiç etki etmezken, mukavemeti 50-80 MPa arttırdığı gözlemlenmiştir. Diğer taraftan A380 alaşımı ile yüksek akışkanlık ve 350 MPa’a kadarlık bir artış elde edilmiştir.

Aluminium and its alloys are the most commonly used alloys in the transportation sector due to their high lightness and strength ratio. The higher corrosion resistance increases the reason why this alloy is preferred. In order to increase the strength values to the desired levels, aluminium alloys are subjected to grain refining with Ti, solution hardening with Mg and Cu and microstructural modifications with Sr. In this study, the relationship between Ag addition to Al-Cu alloy, mould filling ability with Sr addition to Al-Si alloys were investigated. In addition to the traditional spiral tests, newly developed 8-spoke, which is named as octopus design, was used to characterise the fluidity. Ag addition in the Al-Cu alloy (201) has no effect on fluidity particularly in spiral test but it has been observed to increase the strength by 50-80 MPa. On the other hand, high fluidity and strengths up to 350 MPa were achieved by A380 alloy.

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