AlSi10Mg alaşımının içyapı ve mekanik özellikleri üzerine sıcak presleme yönteminin etkisi

Yıl 2024, Cilt: 13 Sayı: 4, 1420 - 1427, 15.10.2024

Murat Beder

https://doi.org/10.28948/ngumuh.1520826

Öz

Bu çalışmada, sıcak presleme yöntemi kullanılarak üretilen ve farklı presleme sıcaklıklarında yoğunlaştırılan AlSi10Mg alaşımının mikroyapısı ve mekanik özelliklerinin incelenmesi araştırılmıştır. Bu amaçla AlSi10Mg alaşımı numunelerine soğuk presleme (N0) ve 450 oC (N1), 500 oC (N2), 550 oC (N3) sıcaklarında sıcak presleme işlemi uygulanmıştır. Soğuk presleme yapılan N0 numunesindeki porozite miktarının N1, N2 ve N3 numunelerine göre yüksek olduğu ve artan sıcaklıkla yoğunluk değerlerinin arttığı, porozite miktarının ise azaldığı belirlenmiştir. Ayrıca, içyapı incelemelerinde artan sıcaklıkla birlikte içyapıdaki silisyum (Si) parçacıklarının giderek küreselleştiği ve yapı içerişe homojen bir şekilde dağıldığı gözlenmiştir. Buna göre, N0, N1, N2 ve N3 kodlu numunelerde en yüksek sertlik değerini yaklaşık %45’lik artış sergileyen N3 numunesi göstermiştir. Buna ilaveten N0, N1, N2 ve N3 numunelerinin yoğunluk değerleri sırasıyla 2.3523, 2.6165, 2.6191 ve 2.6287 gr/cm3 olarak belirlenmiştir. Çekme dayanım değerlerinde ise en yüksek çekme dayanım değeri N3 numunesinde 186 MPa olarak, en düşük çekme dayanım değeri ise N1 numunesinde 156 MPa olarak belirlenmiştir. Buna göre N3 numunesi N1 numunesine göre %20 oranında daha yüksek çekme dayanımı performansı sergilemiştir. Numunelere uygulanan bütün pres sıcakları için çekme ve darbe kırılma yüzeylerinin yarılma düzlemlerinden ve yırtılma sırtlarından oluştuğu belirlenmiştir. Ayrıca, çekme ve darbe deneylerinden elde edilen kırılma yüzeylerinde, artan presleme sıcaklığı ile sertliğin artmasından dolayı yarılma düzlemlerinin genişliklerinin arttığı tespit edilmiştir.

Anahtar Kelimeler

Toz metalürjisi, sıcak presleme, AlSi10Mg alaşımı, Mekanik özellikler

Effect of hot pressing method on the microstructure and mechanical properties of AlSi10Mg alloy

Öz

In this study, the microstructure and mechanical properties of AlSi10Mg alloy produced by hot pressing method and densified at different pressing temperatures were investigated. For this purpose, AlSi10Mg alloy samples were cold pressed (N0) and hot pressed at 450 oC (N1), 500 oC (N2), 550 oC (N3). It was determined that the amount of porosity in the cold pressed N0 sample was higher than the N1, N2 and N3 samples and the density values increased with increasing temperature and the amount of porosity decreased. In addition, it was observed that the silicon (Si) particles in the microstructure became increasingly spherical and homogeneously distributed in the structure with increasing temperature. Accordingly, the highest hardness value in N0, N1, N2 and N3 coded specimens was observed in N3 specimen with an increase of approximately 45 %. In addition, the density values of N0, N1, N2 and N3 samples were determined as 2.3523, 2.6165, 2.6191 and 2.6287 gr/cm3, respectively. In tensile strength values, the highest tensile strength value was determined as 186 MPa in sample N3 and the lowest tensile strength value was determined as 156 MPa in sample N1. Accordingly, N3 specimen exhibited 20 % higher tensile strength performance than N1 specimen. It was determined that the tensile and impact fracture surfaces consisted of cleavage planes and tear ridges for all press temperatures applied to the specimens. In addition, it was determined that the widths of the cleavage planes increased in the fracture surfaces obtained from tensile and impact tests due to the increase in hardness with increasing pressing temperature.

Anahtar Kelimeler

Powder metallurgy, hot pressing, AlSİ10Mg alloys, mechanical properties

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