Effect of Dipping Number on Morphology of Ta2O5 Coatings Made by Sol-Gel Method on AZ91 Mg Alloy

Öz

The study involves the characterization of the Ta2O5 coated AZ91 Magnesium (Mg) alloys produced using the sol-gel method. Mg alloys have a serious potential for use in orthopedic applications due to their lightness and mechanical properties close to the mechanical properties of human bone. However, their corrosion resistance is insufficient for long-term use within the body. Tantalum (Ta), on the other hand, is an element with a high corrosion resistance and does not create a toxic effect on the body thanks to the oxide layer formed on its surface. In this study, it was aimed to cover Ta2O5 in different dipping numbers with the sol-gel method on AZ91 Mg alloys produced by powder metallurgy method and to investigate the effect of this change on the morphology of the coatings. After the samples were coated in different dipping numbers, the change in their morphology was examined using electron microscopy (SEM-EDS) and X-ray diffraction (XRD). As a result of the study, it was observed that the distance between the islets was shortened in the cracked structures encountered in the sol-gel method. With the increasing number of dipping, samples with an average coating thickness of 1, 3 and 7 µm were produced and a more homogeneous coating structure was created on the surface.

Anahtar Kelimeler

• Sol-Gel,Ta2O5,tantalum,Mg alloy

AZ91 Mg Alaşımı Üzerine Sol-Jel Yöntemi ile Yapılan Ta2O5 Kaplamalarda Daldırma Sayısının Kaplamaların Morfolojisine Etkisi

Öz

Yapılan çalışma, sol-jel yöntemi kullanılarak üretilen Ta2O5 kaplı AZ91 Magnezyum (Mg) alaşımlarının karakterizasyonuna yöneliktir. Mg alaşımları hafiflikleri ve insan kemiğinin mekanik özelliklerine yakın mekanik özellikleri nedeni ile ortopedik uygulamalarda kullanım açısından ciddi bir potansiyele sahiptir. Fakat korozyon dayanımları vücut içinde uzun süreli kullanımlar için yetersiz kalmaktadır. Tantal (Ta) ise yüzeyinde oluşan oksit tabakası sayesinde korozyon dayanımı çok yüksek olan ve vücut için toksik etki yaratmayan bir elementtir. Yapılan çalışmada toz metalurji yöntemi ile üretilen AZ91 Mg alaşımları üzerine sol-jel yöntemi ile farklı daldırma sayılarında Ta2O5 kaplanması ve daldırma sayılarındaki bu değişimin kaplamaların morfolojisine etkisinin incelenmesi amaçlanmıştır. Numuneler farklı daldırma sayılarında kaplandıktan sonra morfolojilerindeki değişim elektron mikroskobu (SEM-EDS) ve X-ışını kırınımı (XRD) kullanılarak incelenmiştir. Çalışmanın sonucunda sol-jel yönteminde karşılaşılan çatlaklı yapılarda, adacıklar arası mesafelerin kısaldığı gözlemlenmiştir. Artan daldırma sayısı ile ortalama 1, 3 ve 7 µm kalınlıklarda kaplama tabakasına sahip numuneler üretilmiş ve yüzeyde daha homojen bir kaplama yapısı oluşumu sağlanmıştır.

Anahtar Kelimeler

• Sol-Jel,Ta2O5,Tantal,Mg alaşımı

Kaynakça

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