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Effect of heat treatment and phase change on BFS of two hydroxyapatite ceramic powders
Joint Authors
Sharif, M. Y.
Hasan, M. A.
Mahir, K. A.
Source
Iraqi National Journal of Chemistry
Issue
Vol. 2011, Issue 44 (31 Dec. 2011), pp.526-538, 13 p.
Publisher
University of Babylon College of Sciences
Publication Date
2011-12-31
Country of Publication
Iraq
No. of Pages
13
Main Subjects
Abstract AR
الثبات الحراري و سلوك التلبيد لمسحوقين من هيدروكسيباتيت (PAH) و بالتحديد (BHAP) و (AHAP) بحثت بعد تلبيدها حراريا في مدى درجات حرارة تتراوح ما بين 1450-1100م∘ لمدة ثلاثة ساعات و باستخدام تقنيات XRD و IRS.
تعاقدات النار شخصت بقياس الكثافة الحجمية و الانكماش الناري و قوة اللانثناء ثنائي المحور لها.
لقد لوحظ تحول (BHAP) إلى اوكسي هيدروكسيباتبت (OHAP) عند درجة حرارة ≤ T 1200م∘ و عند درجة حرارة ≤ T 1300 م∘ يبدا بالتفكك ليعطي بيتا ثلاثي كالسيوم فوسفات (β-ΤPC).
كما لوحظ أن (AHAP) ذات استقرارية حرارية أقل من (BHAP) الذي بدوره يتحول إلى (OHAP) عند درجة حرارة ≤ T 1150 م∘ و من ثم إلى (β-ΤPC) عند درجة حرارة ≤ T 1200م∘.
في كلا اللبيديتين يتحول (β-ΤPC) إلى (α-ΤPC) عند درجة حرارة ≤ T 1350 م∘.
كما لوحظ أن فوة الانثناء ثنائي المحور BFS لكلا اللبيدتين ازدادت مع زيادة درجة التلبيد ليصل إلى أعلى قيمة لها عند Ap100-90~M.
Abstract EN
Thermal stability and sintering behaviour of two hydroxyapatite (HAP) powders where designated.
AHAP and BHAP have been investigated at fired sintering temperature range from 1100 to 1450 °C for 3 hrs using XRD and IR spectroscopy.
The fired compacts have been characterised by measuring their bulk density, firing shrinkage and biaxial flexural strength (BFS).
BHAP has been found to transform to oxyhydroxyapatite (OHAP) at T ≥ 1200 °C, and at T ≥ 1300 °C started to decompose to β-tricalcium phosphate (β-TCP).
AHAP has been found to be marginally less stable than BHAP with OHAP forming at T ≥ 1150oC and β-TCP forming at T ≥ 1200 °C.
In both materials, β-TCP transformed to α-TCP at T ≥ 1350 °C.
Maximum densification (∼95 % of theoretical density) occurred at a lower firing temperature for AHAP (1150 °C) than for BHAP (1250 °C), with AHAP also showing a slightly higher firing shrinkage (23 % compared with 20 % for BHAP).
The BFS of both materials have been found to increase with increasing sintering temperature up to 1300 °C, reaching a maximum value of ∼90-100 MPa.
At T ≥ 1300 °C, this is followed by rapid reduction in BFS due to cracks forming as a result of a volume increase associated with the transformation of β-TCP into α-TCP.
It has been concluded that BHAP is marginally more thermally stable than AHAP, while the latter densifies at a lower firing temperature, this is not a disadvantage and comparable properties can be achieved for both powders, although different firing conditions need to be used.
American Psychological Association (APA)
Sharif, M. Y.& Hasan, M. A.& Mahir, K. A.. 2011. Effect of heat treatment and phase change on BFS of two hydroxyapatite ceramic powders. Iraqi National Journal of Chemistry،Vol. 2011, no. 44, pp.526-538.
https://search.emarefa.net/detail/BIM-406659
Modern Language Association (MLA)
Sharif, M. Y.…[et al.]. Effect of heat treatment and phase change on BFS of two hydroxyapatite ceramic powders. Iraqi National Journal of Chemistry No. 44 (2011), pp.526-538.
https://search.emarefa.net/detail/BIM-406659
American Medical Association (AMA)
Sharif, M. Y.& Hasan, M. A.& Mahir, K. A.. Effect of heat treatment and phase change on BFS of two hydroxyapatite ceramic powders. Iraqi National Journal of Chemistry. 2011. Vol. 2011, no. 44, pp.526-538.
https://search.emarefa.net/detail/BIM-406659
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references : p. 537-538
Record ID
BIM-406659