Lantan Oksit Takviyesinin Steatit-Kordiyerit SeramiklerininFiziksel, Mikroyapısal ve Mekaniksel Özellikleri Üzerindeki Etkisi

Bu çalışmada, lantanyum oksit (La 2 O 3 ) takviyeli steatit-ağırlıkça % 20 kordiyerit seramikler (SC20),yüksek enerjili öğütme, soğuk presleme ve sinterlemeden oluşan birleşik bir metot ile üretilmiştir. Farklımiktarlardaki La 2 O 3 takviyesi (ağırlıkça % 0.5, 1, 2, 5 ve 10), proses parametresi olarak kullanılmıştır.Preslenmiş kompakt numuneler, 1250 ve 1300C’de oksit ortamda sinterlenmiştir. Sinterlenmişnumunelerin faz karakterizasyonları ve mikroyapısal özellikleri X-ışınları difraktometresi (XRD), lazerpartikül boyut analiz cihazı ve taramalı elektron mikroskobu (SEM) kullanılarak gerçekleştirilmiştir.Sinterlenmiş numunelerin yoğunluk, açık gözeneklilik ve su emme değerleri Arşimet ve suda kaynatmametotlarından yararlanılarak ölçülmüştür. Mikrosertlik ölçümleri ve basma dayanımı testleri deyapılmıştır. Sonuçlara göre, en yüksek rölatif yoğunluk ( % 99.38) ve en düşük gözeneklilik/su emmedeğerleri, ağırlıkça % 10 La 2 O 3 ile takviye edilmiş 1250C’de sinterlenmiş, ve ağırlıkça % 5 La 2 O 3 iletakviye edilmiş 1300C’de sinterlenmiş SC20 numunelerinde elde edilmiştir. Ayrıca, en yüksek sertlik( 1170 HV) ve basma dayanımı değerleri ( 895 MPa), ağırlıkça % 2 La 2 O 3 ile takviye edilmiş 1300C’desinterlenmiş SC20 numunesi için bulunmuştur.

Effect of Lanthanum Oxide Reinforcement on the Physical, Microstructural and Mechanical Properties of Steatite-Cordierite Ceramics

In this study, lanthanum oxide (La 2 O 3 ) reinforced steatite-20 wt.% cordierite ceramics (SC20) were fabricated by using a combined method of high-energy ball milling, cold pressing and sintering. Different amounts of La 2 O 3 reinforcement (0.5, 1, 2, 5 and 10 wt.%) were used as process parameter. The green compacts were sintered at 1250C and 1300C for 2 h under air. Phase characterizations and microstructural properties of the sintered materials were carried out by using X-ray diffractometer (XRD), laser particle size analyzer and scanning electron microscope (SEM). Density, open porosity and water absorption values of the sintered bodies were measured by Archimedes method and boiling method of impregnation. Microhardness measurements and compressive strength tests were also conducted. According to the results, the highest relative density ( 99.38 %) and the lowest porosity/water absorption values were obtained for the 10 wt.% La 2 O 3 reinforced SC20 sample sintered at 1250C and 5 wt.% La 2 O 3 reinforced SC20 sample sintered at 1300C. Also, 2 wt.% La 2 O 3 reinforced SC20 sample sintered at 1300C had the highest hardness ( 1170 HV) and compressive strength (895 MPa) values.

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