Microstructural and Fractographic Aspects on the Failure Analysis of a Mixed Mode Fractured Ti-6Al-4V Femoral Long Plate

The increasing use of orthopedic surgical implants, both due to the increase in people's longevity and the greater exposure to different types of accidents, has led to the need to develop metallic materials with better performance in this type of application. The aim of this work is to analyze how the failure of a Ti-6Al-4V alloy plate occurred after only 45 days of insertion of this implant in a patient about 50 years old. The use of experimental analysis techniques, such as optical microscopy and scanning electron microscopy (SEM), allowed the conclusion that the plate initially fractured due to fatigue, caused by the concentration of stresses resulting from inadequate machining in the roots of the threads of the holes in plate, proceeding as a brittle transgranular fracture through the cleavage mechanism, due to embrittlement caused by inadequate thermomechanical processing.