Seryum Oksit Katkılı Doğal Obsidyen Camların Mekanik Özellikleri

Öz

Bu çalışmanın amacı, seryum oksidin (ağırlıkça %0,5-10 CeO₂) eklenmesiyle yüksek mekanik özelliklere sahip doğal obsidyen camların üretilmesidir. Obsidyen cam örnekleri geleneksel ergitme metodu ile 1300 ^oC de 2 saat bekletilerek üretilmiştir. Saf ve CeO₂ katkılı obsidyen örneklerinin yoğunluğu Arşimet prensibi ile belirlenmiştir. Numunelerin sertlik ve kırılma tokluğu, Micro-Vickers çentik testi kullanılarak ölçülmüştür. CeO₂ katkılı obsidyen camın XRD desenleri, tüm CeO₂ katkılarında silikon oksit içerdiğini göstermiştir. CeO₂ ilavesi ile obsidyen camın yoğunluğu artmıştır. Mekanik test sonuçları CeO₂'nin obsidyene %1'e kadar ilave edilmesinin sertlikte hafif bir artışa neden olduğunu gösterdi. Ayrıca, obsidyen cam numunelerinin kırılma tokluğu, ağırlıkça %5 CeO₂ ilave edilerek 1,65 ila 1,91 MPa.m^0,5 arasında değişmiştir.  Böylece, obsidyen camların mekanik özellikleri CeO₂ ilavesiyle arttırılabilir.

Anahtar Kelimeler

• Doğal obsidyen cam,Seryum oksit (CeO2),Sertlik,Kırılma tokluğu

Mechanical Properties of Natural Obsidian Glasses Doped with Cerium Oxide

Öz

The objective of this study was to manufacture the natural obsidian glasses, which have high mechanical properties with adding of Cerium oxide at 0.5–10 wt.% CeO₂ to obsidian glass. Obsidian glass samples were produced by conventional melting method at 1300 ^oC for 2h. The densities of pure and CeO₂-added obsidian glass samples were determined by Archimedes' principle. The Hardness and fracture toughness of samples were measured using Micro-Vickers indentation tests. XRD patterns of obsidian glass added with CeO₂ showed that all CeO₂ added samples included silicon oxide. The density of obsidian glass increased with CeO₂ addition. The mechanical test results showed that CeO₂ addition up to 1wt.% content to the obsidian caused a slightly increase in the hardness. Further, fracture toughness of obsidian glass samples changed from 1.65 to 1.91 MPa∙m^0.5 with 5 wt.% CeO₂ addition. As a result, it was found that the mechanical properties of the obsidian glasses could be enhanced through CeO₂ addition.

Anahtar Kelimeler

• Natural obsidian glass,Cerium Oxide (CeO2),Hardness,Fracture toughness

Kaynakça

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