Structural and Mechanical Characterization of Natural Fluoroapatite/3Y-TZP Composites Consolidated by Spark Plasma Sintering

Abstract

This study investigates the structural and mechanical properties of natural fluoroapatite (FAP)/3 mol% yttria-stabilized zirconia (3YSZ) composites consolidated by spark plasma sintering (SPS). Powder mixtures containing 0–100 vol.% 3YSZ were prepared and sintered at optimized temperatures between 800 and 1300 °C under 50 MPa for 10 min. Phase composition, microstructure, density, hardness, and fracture toughness were systematically characterized using XRD, SEM-EDS, Archimedes’ method, and Vickers indentation. High relative densities (96–99%) were achieved within short sintering times. XRD results confirmed the coexistence of tetragonal YSZ and hexagonal FAP phases without detectable secondary reactions. Mechanical properties increased with increasing YSZ content. Pure YSZ exhibited the highest hardness (13.66 GPa) and fracture toughness (5.52 MPa m0.5), while the 95YSZ–5FAP composite retained relatively high mechanical performance (13.46 GPa, 4.42 MPa m0.5). Higher FAP contents led to significant reductions in toughness. The results demonstrate that SPS enables dense bioactive composites while preserving the mechanical integrity of zirconia-rich compositions.

Keywords

• fluorapatite
• ZrO2
• YSZ
• SPS
• composite

Spark Plazma Sinterleme Yöntemiyle Yoğunlaştırılan Doğal Florapatit/3Y-TZP Kompozitlerinin Yapısal ve Mekanik Özelliklerinin İncelenmesi

Abstract

Bu çalışma, spark plazma sinterleme (SPS) yöntemiyle yoğunlaştırılan doğal florapatit (FAP) / %3 mol itriya ile stabilize edilmiş zirkonya (3YSZ) kompozitlerinin yapısal ve mekanik özelliklerini incelemektedir. %0–100 hacim oranında 3YSZ içeren toz karışımları hazırlanmış ve 50 MPa basınç altında, 800–1300 °C arasındaki optimize edilmiş sıcaklıklarda 10 dakika süreyle sinterlenmiştir. Faz bileşimi, mikroyapı, yoğunluk, sertlik ve kırılma tokluğu; XRD, SEM-EDS, Arşimet yöntemi ve Vickers indentasyonu kullanılarak sistematik biçimde karakterize edilmiştir. Kısa sinterleme sürelerinde yüksek bağıl yoğunluk değerleri (%96–99) elde edilmiştir. XRD sonuçları, ikincil reaksiyonlara dair herhangi bir belirti olmaksızın tetragonal YSZ ve hekzagonal FAP fazlarının birlikte varlığını doğrulamıştır. Mekanik özelliklerin, YSZ içeriğinin artmasıyla birlikte yükseldiği belirlenmiştir. Saf YSZ en yüksek sertlik (13,66 GPa) ve kırılma tokluğu (5,52 MPa m0.5) değerlerini sergilerken, %95YSZ–%5FAP kompoziti de görece yüksek mekanik performansını (13,46 GPa, 4,42 MPa m0.5) korumuştur. Daha yüksek FAP içerikleri, kırılma tokluğunda belirgin düşüşlere yol açmıştır. Elde edilen sonuçlar, SPS yönteminin, zirkonya açısından zengin bileşimlerin mekanik bütünlüğünü korurken yoğun ve biyoaktif kompozitlerin üretilmesine olanak sağladığını göstermektedir.

Keywords

• florapatit
• ZrO2
• YSZ
• SPS
• kompozit

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