AlSiCu (LM24) Alüminyum Alaşımında Modifikasyon ve Tane İnceltmenin Mikroyapı ve Mekanik Özelliklere Etkisi

Year 2019, - Cilt:8 - IMSMATEC Özel Sayı, 21 - 28, 15.12.2019

Tansel Tunçay

https://doi.org/10.17100/nevbiltek.634060

Abstract

Bu
çalışmada, AlSiCu alaşımına Stronyum (Sr) ile modifikasyon ve Al5TiB ile tane
inceltme işlemi uygulanmıştır. Çalışmada AlSiCu alaşımı yaklaşık 150-200 ppm Sr
ile modifikasyon ve %0,75 ve 1,5 Al5TiB ile tane inceltme işlemi uygulandıktan
sonra metal ve kum kalıba döküm metodu ile üretilmiştir. Mikroyapı incelemeleri
optik mikroskop (OM), tarama elektron mikroskobu (SEM/EDS analizi), mekanik
özelikler; çekme testi ve sertlik ölçümleri ile değerlendirildi. Sonuç olarak;
optik mikroskop (OM) incelemelerinde metal kalıba dökülen AlSiCu alaşımında
Al-Si ötektiğinin daha homojen ve ince dağıldığı belirlendi. Sr modifikasyonu
ile Al-Si ötektiğinin morfolojisinin değiştirdiği görülmüştür. Al5TiB ilavesi
ile yapının özellikle metal kalıba dökülen alaşımda dendritlerin daha düzenli
olduğu fakat boşluk miktarının arttığı görülmektedir.  Tarama elektron mikroskobu (SEM)
görüntülerinde kum kalıba ve metal kalıba dökülen Al5TiB ile tane inceltme
işlemi uygulanmış alaşımda Al2Cu fazının kum kalıba dökülen alaşım sisteminde
daha fazla olduğu belirlenmiştir.

Keywords

Al-Si-Cu alaşımı, modifikasyon, tane inceltme

The Effect of Modification and Grain Refining on Microstructure and Mechanical Properties of AlSiCu (LM24) Aluminum Alloy

Abstract

The modification process with Strontium
(Sr) and grain refining process with Al5TiB were applied to AlSiCu alloy in
this study. AlSiCu alloy was produced with metal mould and sand mould casting
methods after applying modification process with approximately 150-200 ppm Sr
and grain refining process with 0.75% and 1.5% Al-5TiB. Microstructure analyses
were evaluated by optical microscope (OM) and scanning electron microscope (SEM
/ EDS analysis), and mechanical properties by tensile test and hardness
measurements. As a result, Al-Si eutectic in AlSiCu alloy which was casted into
metal mould was found to be more homogeneous and finely dispersed in accordance
with optical microscope (OM) analyses. It was observed that the morphology of
Al-Si eutectic changed by Sr modification. It was seen with the addition of
Al5TiB that dendrites in structure were more regular in the alloy casted into
metal mould and yet the amount of space increased. When it was examined the
images of the scanning electron microscope (SEM) of the alloys which were
casted into metal and sand moulds and to which grain refining process was
applied, the Al2Cu phase was determined to be more in the alloy system casted
into sand mould.

Keywords

Al-Si-Cu alloys, modification, grain refinement

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