The Fracture Toughness and Brittleness of Au doped YBCO Superconductors

Abstract

In this work, the effect of Au addition on some mechanical properties of YBCO superconductors are analyzed. Five different samples (undoped, 1%, 5%, 15% and 20%) were prepared using the conventional solid state reaction method. The experimental results of the microhardness measurements are used to obtain the yield strength, Young’s modules, fracture toughness and brittleness index. These mechanical properties mentioned above are extracted by using the proportional specimen resistance (PSR) model. The mechanical properties of the samples were found to be load dependent. The yield strength, Young’s modules, brittleness index and fracture toughness values increase with decreasing test load and decreases with increasing Au content. The possible reasons for the observed degradation in the mechanical properties due to Au addition are discussed.

Keywords

• Au addition,Fracture toughness,YBCO

Au katkılı YBCO süperiletkenlerin kırılma tokluğu ve kırılganlıkları

Abstract

Bu çalışmada, Au ilavesinin YBCO süper iletkenlerinin bazı mekanik özelliklerine etkisi incelenmiştir. Geleneksel katı hal reaksiyon metodu kullanılarak beş farklı numune (katkısız, % 1, % 5, % 15 ve % 20) hazırlanmıştır. Mikro sertlik ölçümlerinin deneysel sonuçları, akma dayanımı, Young modülleri, kırılma tokluğu ve kırılganlık indeksi elde etmek için kullanılmıştır. Yukarıda belirtilen bu mekanik özellikler PSR modeli kullanılarak elde edilmiştir. Numunelerin mekanik özelliklerinin yüke bağlı olduğu bulunmuştur. Akma dayanımı, Young’s modulus, kırılganlık indeksi ve kırılma tokluğu değerlerinin azalan test yükü ile arttığı ve artan Au içeriği ile azaldığı gözlemlenmiştir. Au ilavesi nedeniyle mekanik özelliklerde gözlenen bozulmanın olası nedenleri tartışılmıştır.

Keywords

• Au katkılama,kırılma tokluğu,YBCO

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