Selective laser melting of CoCr alloys in biomedical application: A review

• Published in: Radiation Technologies and Applications in Materials Science pp. 287 - 309
• Main Authors: Saini, J. S., Dowling, Luke, Trimble, Daniel, Singh, Sachin
• Format: Book Chapter
• Language: English
• Published: United Kingdom CRC Press 2023; Taylor & Francis Group
• Edition: 1
• Subjects: SLM Machine; Pre-process Parameters; Cast Specimens; SLM; Artificial Saliva Solution; SLM Sample; SLM Technique; Artificial Saliva; CoCrMo Alloy; LMD; Corrosion Resistance; Subtalar Joints; SEM Image; Biocompatible Metals; SLM Specimen; SLM Technology; CoCr Alloys; CCW; SLM Process; Biocompatible Alloy; Femoral Stems; Ion Release; Laser Scanning Speed; PIII; Cobalt Chromium Alloys
• ISBN: 9781032343945; 1032343958; 103234394X; 9781032343952
• DOI: 10.1201/9781003321910-11

Additive manufacturing (AM) is used to describe the fabrication of functional, end use components in a layer-by-layer manner based upon a 3D design model. It enables the fabrication of complex geometries which are difficult to manufacture using alternative methods. The development in AM technology led to the creation of three typical processes in terms of laser sintering, laser melting and laser metal deposition. Among them, the selective laser melting (SLM) is the most in-demand approach, as its potential of rapid manufacturing of complex and unique parts have been demonstrated. Recently, cobalt-chromium (CoCr) alloys have gained a lot of interest in the research community due to their greater hardness, mechanical strengths, and biocompatibility. CoCr alloys are widely used in biomedical applications as they are the hardest known biocompatible alloy along with good tensile and fatigue properties. However, the fabrication processes for these alloys, such as casting, cutting, and plastic works, are usually difficult because of their high melting point, hardness, and limited ductility. Moreover, the method which is used to manufacture the alloy plays a very important role in the mechanical and metallurgical properties of the resulting component that needs to be accurately controlled for desired quality. SLM has been used to manufacture the components from CoCr alloys due to its capability to control the different process parameters accurately. The present review deals with the use of SLM-built CoCr alloys in biomedical applications. Cobalt-chromium (CoCr) alloys have gained a lot of interest in the research community due to their greater hardness, mechanical strengths, and biocompatibility. Selective laser melting (SLM) has been used to manufacture the components from CoCr alloys due to its capability to control the different process parameters accurately. This chapter deals with the use of SLM-built CoCr alloys in biomedical applications. Compared to traditional casting methods, the SLM technique offers advantages such as low manufacturing cost, high density of products, high-dimensional accuracy, reduced operator errors, accuracy of the products, improved electrochemical characteristics and prevention of casting defects. The SLM metal copings have been reported to have satisfactory mechanical and chemical properties. There are mainly three well known and vastly implemented biocompatible metals viz. stainless steel, cobalt chromium alloys, titanium, and its alloys. The high performance, good aesthetics, and high density of SLM-manufactured products make the process suitable for CoCr medical applications.