Pull out Performance of Medical Screws used in Orthopaedic Surgeries

Öz

In this study, a new medical bone screw was designed and manufactured by Ti6Al4VELI GR23 material and tested in accordance with the ATSM F 543-02 test procedure experimentally. This test is used to measure the axial tensile force required to fail or remove a bone screw from a defined material. Concurrently, 3-D Finite Element Analysis (FEA) models of these medical bone screws were developed to simulate and biomechanically evaluate the pull-out forces and stiffness of the screw samples using FEA software ANSYS. Obtained results from the FEA models are in reasonable agreement with the experimental data on the pull-out strength of the medical bone screw. Results from FE models are experimentally verified.

Anahtar Kelimeler

• Medical screws,Finite element analysis (FEA),Pull-out,Biomechanics

Ortopedik Operasyonlarda Kullanılan Medikal Vidaların Sıyırma Performansı

Öz

Bu çalışmada, Ti6Al4Veli GR23 malzemesi kullanılarak yeni bir medikal vida tasarlanmış, ASTM-543-02 test prosedürüne uygun test edilmiş ve üretilmiştir. Bu testte tanımlanan bir malzemeden vidanın kırılmasını veya kemik malzemeden ayrılmasına neden olan kritik eksenel kuvvet hesaplanır. Aynı zamanda, tasarlanan vidanın üç boyutlu sonlu elemanlar modeli ANSYS programı kullanılarak sıyırma kuvvetleri ve dayanımları değerlendirilmek ve simule edilmek için oluşturuldu. Sonlu elemanlar modelinden elde edilen sonuçlar deneysel sıyırma mukavemeti sonuçlarıyla uygunluk göstermiştir. Böylece sonlu elemanlar ile elde edilen sonuçlar deneysel olarak doğrulanmıştır.

Anahtar Kelimeler

• Medikal vidalar,Biyomekanik,Sonlu elemanlar yöntemi,Sıyırma

Kaynakça

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