Politeknik Dergisi 2147-9429 Gazi University 10.2339/politeknik.712759 Engineering Mühendislik Compression and Compression-Shear Strength of Trabecular Metal Structures Produced from Ti6Al4V ELI Alloy with Selected Laser Melting Seçimli Lazer Ergitme İle Ti6Al4V ELI Alaşımından Üretilen Trabeküler Metal Yapıların Basma Ve Basma-Kayma Dayanımlarının İncelenmesi https://orcid.org/0000-0002-4932-9654 Balcı Arif GAZİ ÜNİVERSİTESİ, MÜHENDİSLİK FAKÜLTESİ, MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ https://orcid.org/0000-0001-9434-5955 Aycan Mehmet Fatih GAZİ ÜNİVERSİTESİ, MÜHENDİSLİK FAKÜLTESİ, MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ https://orcid.org/0000-0003-2403-155X Usta Yusuf GAZİ ÜNİVERSİTESİ, MÜHENDİSLİK FAKÜLTESİ, MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ https://orcid.org/0000-0001-6352-8302 Demir Teyfik TOBB ETU, Mühendislik Fakültesi, Makina Mühendisliği Bölümü 09 01 2021 24 3 903 914 04 02 2020 05 16 2020 Copyright © 1998, Journal of Polytechnic 1998 Journal of Polytechnic

Porous structures that can provide properties of material and have started to be needed for production of regenerative biomedical products in orthopedics. The stress-shielding effect, which occurs as a result of remarkable strength difference from solid materials to bone, causes loss of biomedical implants. Porous materials can be designed according to conditions with advantages of additive manufacturing and manufacturing can be made by copying natural geometries. In the study, the geometries obtained by copying the trabecular bones taken from femur and vertebra regions of a sheep by Micro-CT compared to studies on reproducibility and strength of designable unit cell geometries in the literature were produced by selective laser melting from Ti6Al4V ELI alloy. Compression and compression-shear strengths of samples were examined. The elasticity module was obtained from the compression tests and found 3±0.25 GPa on the femur samples and 2±0.15 GPa on the vertebra samples. It was found that the compatibility of finite element analysis with the test results was admirable. As the trabecular metal takes its geometry from bone structure, it is concluded that it is an interface material with high fusion capability for biomedical products by supporting bone inward growth behavior and decreasing stress shielding effect.

Üretildiği malzemenin dayanım, biyolojik ve yorulma gibi özelliklerini kullanım alanına uygun olarak şartlandırabilen gözenekli yapılara ortopedi alanında özellikle onarıcı biyomedikal ürün üretimi için gereksinim duyulmaya başlanmıştır. Dolu malzemelerin kemik ile dayanım farkının fazla olması sonucu ortaya çıkan gerilme kalkanı etkisi biyomedikal ürün kaybına sebep olmaktadır. Eklemeli imalat yöntemlerinin sağladığı avantaj sayesinde gözenekli malzemeler koşullara uygun olarak tasarlanabilmekte veya doğal yapıya sahip geometrilerin kopyalanması ile üretim yapılabilmektedir. Literatürün genelinde yer alan tasarlanabilir birim hücre geometrilerinin üretilebilirliği ve dayanımı hakkındaki çalışmaların aksine yapılan çalışmada koyuna ait femur ve vertebra bölgelerinden alınan trabeküler kemiklerin Mikro-CT ile kopyalanması sonucu elde edilen geometriler Ti6Al4V ELI alaşımından seçimli lazer ergitme (SLE) metodu ile üretilmiştir. Yapılan üretimlerin basma ve basma-kayma dayanımları incelenmiştir. Destek yapılar kullanılmadan yapılan üretim sonrası karşılaşılabilecek üretim değişimleri göz önünde bulundurularak trabeküler yapının üretiminde 1:1, 1:1,10 ve 1:1,20 ölçekli geometriler kullanılmıştır. Yapılan basma testleri sonucunda elastisite modül femur numunelerinde ortalama 3±0,25 GPa ve vertebra numunelerinde 2±0,15 GPa olarak elde edilmiş olup analizlerin deney sonuçları ile uyumluluğunun yüksek olduğu görülmüştür. Çalışma kapsamında üretilen trabeküler metal yapının biyomedikal ürünlerde kullanılması durumunda sahip olduğu düşük elastisite modül değerleriyle gerilme kalkanı etkisini azaltacağı ve doğal kemik geometrisi avantajı ile kemiğin içe doğru büyüme davranışını destekleyeceği sonucuna varılmıştır.

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