AM Serisi Magnezyum Alaşımlarının Termal Özellikleri

Öz

Bu makale, AM serisi döküm magnezyum alaşımlarının termal özellikleri (termal yayılma ve termal iletkenlik) üzerine deneysel araştırmalar sunmaktadır. Alaşımlardaki Al içeriğindeki değişimin (2'den 9 Al’e ve sabit 0.5 Mn, ağırlıkça %) ısıl özellikler, yoğunluk ve sertlik üzerindeki etkileri karşılaştırmalı olarak analiz edilmiştir. Alaşımların mikroyapısında bulunan intermetalik fazların (Mg17Al12 ve Al8Mn5) 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 25 °C’den- 400 °C’e kadar). En yüksek termal difüzivite AM20 alaşımında ve en düşük termal difüzivite ise AM90 alaşımında gözlenmiştir.

Anahtar Kelimeler

• Thermal Difüzivite
• Termal İletkenlik
• Yoğunluk
• Magnezyum Alaşımları
• Sertlik

Thermal Properties of AM Series Magnesium Alloys

Öz

This paper presents experimental investigation on thermal properties (thermal diffusivity and thermal conductivity) of AM series cast magnesium alloys. The effects of the changing in Al content (from 2 to 9 Al and constantly 0.5 Mn, wt. %) in the alloys on thermal properties, density and hardness were comparatively analyzed. It was observed that intermetallic phases (Mg17Al12 ve Al8Mn5) 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 AM20 alloy and the lowest thermal diffusivity were observed on AM90 alloy.

Anahtar Kelimeler

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

Kaynakça

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