Effect of the carbamide content on the preparation of porous Ti6Al4V using arc plasma sintering method

Abstract

Ti6Al4V has been widely used as the orthopedic implant material due to its excellent mechanical properties and biocompatibility. However, failure in the long-term use of Ti6Al4V implants may occur as a result of the “stress shielding effect” which caused by the difference elastic modulus between the implant and the bone. Therefore, porous Ti6Al4V is developed to achieve lower elastic modulus but maintain other interesting properties. To produce porous Ti6Al4V, powder metallurgy (PM) using the space holder can be chosen as a pore former. The problem of Ti6Al4V fabrication may arise due to the high reactivity of titanium at a high temperature. Therefore, PM using arc plasma sintering (APS) method is proposed to reduce the risk of oxidation and contamination in porous Ti6Al4V manufacturing in a relatively shorter time. In this study, carbamide was varied (0-20 wt.%) to prepare porous Ti6Al4V while the APS processing parameters were kept at a constant value (current of 40 A, sintering time of 8 minutes). The as-sintered specimens were then characterized by scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDS) analysis and X-ray diffraction (XRD). It was shown that the carbamide can be used to fabricate porous Ti6Al4V via the APS method. Addition of carbamide was in line with the increasing of porous formation in the alloy. From this study, Ti-15 Carb was shown to be a potential porous Ti6Al4V alloy due to its highly distributed pore structure while having less contamination and oxidation.