Bülent AKTAŞ, Şerife YALÇIN, Abuzer AÇIKGÖZ, Rahime ŞERBETÇİ

Seryum Oksit Katkılı Doğal Obsidyen Camların Mekanik Özellikleri

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.m0,5 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

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∙m0.5 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.

Keywords:

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

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