AS Serisi Magnezyum Alaşımlarının Termal Davranışları

Öz

Bu makale, AS serisi döküm magnezyum alaşımlarının ısıl davranışları (ısıl yayılma ve ısıl iletkenlik) üzerine deneysel bir araştırma sunmaktadır. Alaşımlardaki Al içeriğindeki değişimin (1- 9 Al ve 1 Si sabit, ağırlıkça %) ısıl özellikler, yoğunluk ve sertlik üzerindeki etkileri karşılaştırmalı olarak analiz edilmiştir. Alaşımların mikroyapısında bulunan intermetalik fazların (Mg17Al12 ve Mg2Si) ısıl yayınım, ısıl iletkenlik, yoğunluk ve ayrıca sertlik üzerine etkisi olduğu görülmüştür. Alaşımın ısıl özellikleri, alaşımdaki Al içeriği arttıkça azalmıştır. Alaşımların termal özellikleri artan sıcaklıkla artmıştır (sıcaklık değişimi 25 °C - 400 °C arası). En yüksek termal yayılma AS21 alaşımında ölçülmüştür ve en düşük termal yayılma AS91 alaşımında gözlenmiştir.

Anahtar Kelimeler

• AS Serisi Magnezyum Alaşımları
• Termal Yayılma
• Termal İletkenlik
• Yoğunluk
• Sertlik

Thermal Behaviors of AS Series Magnesium Alloys

Öz

This paper presents experimental investigation on thermal behaviors (thermal diffusivity and thermal conductivity) of AS series cast magnesium alloys. The effects of the changing in Al content (from 1 to 9 Al and constantly 1 Si, wt.%) in the alloys on thermal properties, density, and hardness were comparatively analyzed. It was observed that intermetallic phases (Mg17Al12 and Mg2Si) found in the microstructure of the alloys have an effect on thermal diffusivity, thermal conductivity, density and also hardness. The thermal properties of the alloys were decrease with increasing Al content in the alloy. The thermal properties of the alloys were increase with increasing temperature (the temperature range from 25°C to 400°C). The highest thermal diffusivity was measured on AS21 alloy and the lowest thermal diffusivity were observed on AS91 alloy.

Anahtar Kelimeler

• AS Series Magnesium Alloys
• Thermal Diffusivity
• Thermal Conductivity
• Density
• Hardness

Kaynakça

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