A Comparative Study on Wear and Thermal Behaviors of AZ91, AS91 and AM90 Magnesium Alloys

Öz

This paper is a comparative study on wear resistance and thermal behaviors of AZ91, AS91 and AM90 (Mg-9Al-X) cast magnesium alloys. The effects of the changing in third alloy components (X;1 Zn, 1 Si, 0.5 Mn, respectively, and constant 9 Al, wt.%) in these alloys on wear resistance, thermal properties and densities were comparatively analyzed. It was seen that intermetallic phases (Mg17Al12 in AZ91, Mg2Si in AS91 and Al8Mn5 in AM90) found in the microstructure of the alloys have an effect on hardness, densities, wear resistance and thermal properties. The thermal properties of the alloys were increase with increasing temperature (the temperature range from 25°C to 400°C). The highest thermal diffusivity were measured on AZ91 alloy and the lowest thermal diffusivity were measured on AM90 alloy. On the other hand, the highest wear resistance was observed in AM90.

Anahtar Kelimeler

• AZ91, AS91, AM90 Magnesium Alloys
• Wear
• Thermal Diffusivity
• Thermal conductivity
• Density

AZ91, AS91 ve AM90 Magnezyum Alaşımlarının Aşınma ve Isıl Davranışları Üzerine Karşılaştırmalı Bir Çalışma

Öz

Bu makale, AZ91, AS91 ve AM90 (Mg-9Al-X) döküm magnezyum alaşımlarının aşınma direnci ve termal davranışları üzerine karşılaştırmalı bir çalışmadır. Bu alaşımlardaki üçüncü alaşım bileşenlerindeki değişimin (X; sırasıyla, 1 Zn, 1 Si, 0.5 Mn ve sabit 9 Al, % ağırlıkça) alaşımların aşınma direnci, ısıl özellikleri ve yoğunlukları üzerindeki etkileri karşılaştırmalı olarak analiz edilmiştir. Alaşımların mikroyapısında bulunan intermetalik fazların (AZ91'de Mg17Al12, AS91’de Mg2Si ve AM90’da Al8Mn5) sertlik, yoğunluk, aşınma direnci ve ısıl özellikler üzerinde etkili olduğu görülmüştür. Alaşımların termal özellikleri artan sıcaklıkla artmıştır (sıcaklık değişimi 25 °C'den 400 °C'e kadar). En yüksek termal yayılma AZ91 alaşımında, en düşük termal yayılma ise AM90 alaşımında ölçülmüştür. Öte yandan, en yüksek aşınma direnci AM90'da gözlenmiştir.

Anahtar Kelimeler

• AZ91, AS91, AM90 Magnezyum Alaşımları
• Aşınma
• Termal Yayılma
• Termal İletkenlik
• Yoğunluk

Kaynakça

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