Portfolio Project

• Material Selection for Hip Implant

• Oct 2016 - Dec 2016

Human joints are complex structures capable of functioning under severe conditions due to the combined efforts of articular cartilage, namely a load-bearing connective tissue that covers bones, and synovial fluid, secreted within the joint area. Over the last decades, the growth in the longevity of the population has led to a rapidly increasing necessity of surgical operations involving prosthesis implantation. Implants are medical devices manufactured to support, substitute or enhance missing or damaged biological structures. They can be roughly categorized into groups by their application, like cardiovascular, orthopaedic, etc. Lately, large achievements have been developed in total joint replacement procedures: by this technique, metal, ceramic or polymeric artificial materials replace the entire load-bearing system. Indeed, although minor surgical treatments are done to provide temporary relief, the ultimate step is to substitute the dysfunctional joints and reinforce the bones. In this project, the hip implant was investigated by taking into account the femoral stem, femoral head, Plastic liner & Acetabular component. More specifically, the selection of metals for these components is the primary objective of the study, the most used in history and a recent one are accounted for the evaluation. Initially, based on the desired functionalities a set of criteria has been defined, specifically, focusing on the material properties with given high importance to the Biocompatibility such as corrosion rate, Toxicity of metal ions. Secondarily, material strength characteristics such as Material wear, Fatigue were considered for Steel alloys, Cobalt base alloys, Titanium alloys & Metallic foam. By considering these aspects into account, assessment has been carried out by employing a QFD4 Matrix.