ANALYSIS OF HIP PROSTHESIS PRODUCTION WITH FORGING USING THE FINITE ELEMENT METHOD

Öz

Hip prostheses used to fulfill injured or fractured limbs are made by machining, casting and plastic forming. Machining is the most commonly used one. However, there are many disadvantages such as high product cost in machining. Plastic forming methods provide more effective and durable implant production than machining. In this study, hip prosthesis with a complex geometry produced by forging were analyzed using the Finite Element Method (FEM). For this purpose, three-dimensional complex geometry was designed and then, FEM analyses were performed using MSC SIMUFACT 10 software. Factors affecting the production were defined as: temperature, friction coefficient and the pressing velocity. Stress distributions, temperature changes, die wears and punch forces applied to the die were examined. As a result of the study, the most suitable parameters were obtained as 500°C, 0.05 coefficient of friction and 2mm/s die velocity. Also, the obtained FEM results were examined by regression analyses.

Anahtar Kelimeler

• Hip prosthesis, Forging, Ti6Al4V, Finite Element Method, Regression analysis

DÖVME İLE KALÇA PROTEZİ ÜRETİMİNİN SONLU ELEMANLAR YÖNTEMİYLE İNCELENMESİ

Öz

Yaralı veya kırık uzuvlarn işlemini yerine getirmek için kullanılan kalça protezleri döküm, plastik şekillendirme ve talaşlı imalat yöntemleri ile üretlmektedir. Bu konuda talaşlı imalat en yaygın olarak kullanılan yöntemdir. Ancak, talaşlı imalat yönteminin yüksek ürün maliyeti gibi bir çok dezavantajları vardır. Plastik şekillendirme yöntemleri daha etkin ve dayanıklı implant üretimi sağlar. Bu çalışmada, karmaşık geometriye sahip kalça protezinin dövme ile üretimi Sonlu Elemanlar Yöntemi (FEM) kullanılarak analiz edilmiştir. Bu amaçla, kalça protezin üç boyutlu modeli tasarlanmıştır ve daha sonra, FEM analizler MSC SIMUFACT 10 yazılımı kullanılarak yapılmıştır. Sıcaklık, sürtünme katsayısı ve presleme hızı üretimi etkileyen faktörler olarak tanımlanmıştır. Gerilme dağılımları, sıcaklık değişiklikleri ve kalıba uygulanacak kuvvet miktarı değerleri incelenmiştir. Çalışmanın sonucunda, en uygun parametreler 500°C sıcaklık, 2 mm/s presleme hızı ve 0.05 sürtünme katsayısı olarak elde edilmiştir. Aynı zamanda, elde edilen FEM sonuçları regresyon analizi ile incelenmiştir

Anahtar Kelimeler

• Kalça Protezi, Dövme, Ti6Al4V, Sonlu elemanlar Yöntemi, Regresyon analizi

Kaynakça

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