INVESTIGATION ON THE EFFECT OF RARE EARTH (RE) CATION TO THE (RE+Ca)SiAlON GLASSES

Year 2012, Volume: 13 Issue: 2, 127 - 134, 31.01.2013

Cem Orhun Emrah Dölekçekiç

Abstract

The main purpose of this study was to determine the change in density, glass transition temperature (Tg) and hardness as a result of compositional modifications in the (RE+Ca)SiAlON oxynitride glasses (RE= Er, Nd, Sm, Eu, Dy, Yb) with a cation ratio in eq% of (1+27):56:16 = (RE+Ca):Si:Al. The amount of nitrogen was kept constant (N=5 eq %).

Additionally other series of the (Er+Y):Si:Al:O:N glasses with cation composition  3+25):56:16 were prepared with different amount of nitrogen (where N= 0, 5, 10 eq %) to observe the effect of nitrogen to glass transition temperature. X-Ray diffraction patterns proved that all produced glasses were amorphous.

Tg and hardness results of (RE+Ca)SiAlON glasses were revealed that there is a linear relationship between cation field strength (CFS). Density results versus molecular weight and CFS were presented. Additionally, glass transition temperatures of the (Er+Y)SiAlON glasses were further increased with the increasing nitrogen content in the structure. These results are also compared with (RE+Ca)SiAlON glass series.

Keywords

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NADİR TOPRAK ELEMENTİ KATYONLARININ (RE+Ca)SiAlON CAMLARINA ETKİSİNİN İNCELENMESİ

Abstract

Bu çalışmanın ana amacı katyon oranı eşdeğer yüzdece (eq %), (1+27):56:16=(RE+Ca):Si:Al olan
(RE+Ca)SiAlON oksinitrür camlarında yoğunluk, cam geçiş sıcaklığı ve sertlik değişimlerinin bile-
şimsel değişikliklere bağlı olarak incelenmesidir. (RE+Ca)SiAlON camlarının azot değerleri sabit tutulmuştur
(N=5 eq %).
Ayrıca, katyon bileşimi (3+25):56:16 olan (Er+Y):Si:Al camlar, azotun Tg’ye etkisini gözlemlemek
amacıyla farklı azot oranlarıyla hazırlanmıştır (N= 0, 5, 10 eq %).
(RE+Ca)SiAlON camlarının Tg ve sertlik sonuçları katyon alan mukavemeti (CFS) değerlerine
bağlı olarak lineer bir ilişkiyle açıklanmıştır. Yoğunluk sonuçları ise moleküler ağırlık ve CFS değerlerine
karşı sunulmuştur. Ayrıca, (Er+Y)SiAlON camlarının cam geçiş sıcaklıkları artan azot miktarına
göre artış göstermiştir. Bu sonuç (RE+Ca)SiAlON serisiyle kıyaslanmıştır.

Keywords

Oksinitrür cam, Nadir element etkisi, Azot etkisi, Katyon alan mukavemeti

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