AZ91 magnezyum alaşımının sol-jel yöntemiyle hidroksiapatit kaplanması

Year 2017, Volume 23, Issue 8, 954 - 956, 28.12.2017

Sevda Albayrak Hanifi Çinici Recep Çalın Canser Cömert

Abstract

Bu çalışmada amaç; biyomedikal uygulamalarda kullanılmak üzere mevcut biyomalzemelerden daha hafif, biyolojik saldırılara karşı dirençli ve kemik yapısına benzer, doku ile uyumlu bir malzeme üretebilmektir. Hafiflik biyomalzeme uygulamalarında son derece önemlidir, çünkü paslanmaz çelik ve bunun gibi ağır metalik alaşımlar vücutta kullanıldığında implant çevresindeki dokulara zarar vererek enfeksiyona sebep olabilmektedir. AZ91 Mg alaşımının hafifliği büyük bir avantaj olsa da vücutta kullanmak için yeterli mukavemete sahip değildir ve biyolojik ortamda bozunmaktadır. AZ91 Mg alaşım tozları 320 °C sıcaklık ve 275 MPa basınçta sıcak pres yöntemi ile preslendikten sonra, yeterli dayanımı sağlamak ve bozunmasını engellemek amacıyla sol-jel ve dip coating metoduyla yüzeyi farklı daldırma sayılarında hidroksiapatit ile kaplanmış ve 400 °C’de sinterlenmiştir. Kaplanan numunelerin yüzey morfolojileri SEM; faz yapıları ise XRD ile incelenmiştir.

Keywords

AZ91 magnezyum alaşımı, Hidroksiapatit, Sol-jel Yöntemi

Hydroxyapatite coating on AZ91 magnesium alloy via sol-gel method

Abstract

Producing a material lighter than available biomaterials, having corrosion-resistance to biological attacks and histocompatible similar to the bone structure in order to use in biomedical applications is the purpose of this study. Lightness is extremely important in biomedical applications because stainless steel and many of the similar heavy metallic alloys can lead to infection by causing harm to tissues around the implant when it is used in the body. Although the lightness of AZ91 Mg alloy is an advantage, it is not strength enough to use in human body and it degrades in biological environment. After AZ91 Mg alloy powders were pressed with unidirectional hot pressing machine under 275 MPa pressure and 320 °C temperature, their surfaces were coated with hydroxyapatite to provide sufficient strength and prevent the degradation of specimens using sol-gel and dip coating method with different dipping number. Then the specimens were sintered at the temperature of 400 °C. The surface morphologies and phase structures of coated specimens were analyzed with SEM and XRD, respectively.

Keywords

AZ91 magnesium alloy, Hydroxyapatite, Sol-gel Method

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