AMORF/NANOYAPILI Mg-ESASLI İNCE FİLMLERİN HİDROJEN DEPOLAMA UYGULAMALARI İÇİN ÇOK ELEMENTLİ KAYNAKLARDAN ÜRETİMİ

Year 2013, Volume: 28 Issue: 1, 1 - 10, 01.03.2013

Hasan Akyıldız Tayfur Öztürk

Abstract

Bu çalışmada, Mg-esaslı amorf/nanoyapılı ince filmler ısıl buhar çöktürme yoluyla üretilmiştir. Tüm filmler, toz metalurjisi yöntemleri ile hazırlanmış çok elementli kaynakların buharlaştırılması ile elde edilmiştir. Hazırlanan kaynaklar Mg-Cu, Mg-Cu-Ni, Mg-Cu-Al, Mg-Cu-Al-Ni şeklindedir. Üretilen kaynakların, sinterlendikleri sıcaklıktaki denge fazlarını ve serbest halde elementleri içerdikleri görülmüştür. Buharlaştırma sonrası ise sistemdeki fazların büyük oranda zayıflaştığı/amorflaştığı, hidrürlemenin ise incelmeyi daha da fazla artırdığı tespit edilmiştir. Çalışma, önerilen yöntemin ısıl buharlaştırma ile amorf/nanoyapılı film oluşturmaya uygun olduğunu göstermekle birlikte, bu tarz filmlerde, hidrojen depolama davranışının takibinde, X-ışınları kırınımından farklı yöntemlerin kullanılması gerekliliğini ortaya koymaktadır.

Keywords

Hidrojen Depolama, İnce Filmler, Toz Metalurjisi, Mg-Cu, Mg-Cu-Ni

Production of Mg-Based Amorphous/Nanostructured Thin Films From Multi-Elemental Sources for Hydrogen Storage Applications

Abstract

A study was carried out for the production of Mg-based amorphous/nanostructured thin films from multi-elemental evaporation sources via thermal evaporation. Sources produced were Mg-Cu, Mg-Cu-Ni, Mg-Cu-Al, Mg-Cu-Al-Ni and all prepared by traditional powder metallurgy routes. The powder compacts in the as-sintered state were made of equilibrium phases and individual elements, but upon deposition, due to interaction in the vapor phase, refined structure yielded amorphous like thin films. The structure further refined by the sorption of hydrogen. The study showed that the powder metallurgy approach is applied with success to deposit amorphous/nanostructured thin films via thermal evaporation, and further implies that if the phase analysis were to be used as an evaluation method for hydrogen sorption characteristics, some other techniques instead of X-ray diffraction analysis have to be considered

Keywords

Hydrogen Storage, Thin Films, Powder Metallurgy, Mg-Cu, Mg-Cu-Ni

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