A Comparative Study of Surface Cleaning Treatments for 3D Printed Medical Implants

Abstract

In the field of Additive Manufacturing (AM), one of the major applications of laser-based 3D metal printing is the creation of custom implants for medical purposes. However, a significant challenge in the manufacturing of implants using Selective Laser Melting (SLM) is the formation of partially melted particles on the surface of medical implants. These particles result in a multitude of issues including plurality of structurally weak points on the designed implants, obstruction of important design features, and possibility of dislodgement over the service life span, thereby posing a threat to the recipient. To address the above challenges, it is imperative to develop a simple but effective surface cleaning method to remove partially melted particles from the surface without damage to the designed medical implants. In this work, a comparative study was conducted to investigate the effect of both chemical and electro-plasma based cleaning processes on the removal of partially melted particles from the surfaces of 3D printed Ti-6Al-4V medical screw implants. These techniques include chemically polishing implants with HF-HNO3 acid solutions and using an electro-plasma based cleaning process. With the field of additive manufacturing rapidly expanding, this work offers valuable insight on proper post-process treatment of 3D printed parts for future medical purposes in biomedical fields.