Customized implants with specific properties, made by selective laser melting

Abstract

Purpose -The purpose of this paper was to present how customized implants could be made with specific properties, by setting different values of the laser power, within the selective laser melting (SLM) process. A detailed case study was undertaken and a new multi-structured femoral prosthesis was designed and analyzed, to simulate its behavior for a specific case study. Design/methodology/approach -The materials and manufacturing methods are presented, with details regarding the SLM process, using the Realizer 250 machine. The laser power was varied between 50 and 200 W, thus obtaining samples with different physical and mechanical characteristics. All those sample parts were characterized and their properties were measured. Findings -A practical methodology was found to produce multi-structured implants by SLM. Significant changes of the porosity and properties were found, when modifying the laser power at the SLM machine. The studies have indicated an open porosity varying between 24.810.83 per cent. Tensile tests of the samples showed Young's modulus values varying between 13.5 and 104.5 GPa and an ultimate stress between 20.2 and 497.5 MPa. Research limitations/implications -There is no Additive Manufacturing (AM) machine available, to work with different laser power values, in different regions of the same section of the implant. Hence, a multi-structured implant cannot be obtained directly.Practical implications -The prosthesis should be specifically designed to contain separate models/regions to be made with appropriate laser power values. Originality/value -This paper presents a new method to design and manufacture a multi-structured implant, using the existing AM equipment. A detailed case study is presented, showing the design procedure, the way to simulate its behavior and the methods to produce the implants by SLM.

In situ morphology-based defect detection of selective laser melting through inline coherent imaging

“…Additionally, similar studies have investigated properties of parts manufactured from biomedical alloys (Vandenbroucke and Kruth, 2007). Biomedical-based research has progressed to investigating strategies to produce patient-specific biomedical implants (Leordean et al, 2015) and to the production of dental crowns and bridges (Gebhardt et al, 2010).…”

Prediction of porosity in metal-based additive manufacturing using spatial Gaussian process models

“…It is regarded by some as a potential game changer, especially with the advent of AM technologies that can process advanced metallic materials and alloys such as stainless steel [4][5][6], Ti-6Al-4V [7,8], and nickel-based alloys [9]. In contrast to the limited application of polymer-based AM in producing visualization or functional prototypes to accelerate product development in the early 1980s, metal-based AM is now used to produce parts for direct use such as the fuel nozzle that GE Aviation will use in their LEAP engine [10,11], Lockheed's blead air leak detector [12], and biomedical cranial and hip implants [13][14][15].…”

Mechanical stability of custom-made implants: Numerical study of anatomical device and low elastic Young's modulus alloy

“…In many cases, custommade (or anatomical) implants have shown excellent fit to the defect, reduction of the rate of implant failure, and high patient satisfaction [2,8,9]. Therefore, the recent developments of additive manufacturing with titanium-based alloys have significantly facilitated the fabrication of these kinds of implants [10,11]. This type of customized solution can be applied to a large field of traumas, as cranio-facial for bone augmentation devices [12], or mandible prosthesis [13].…”

“…In this work, finite elements method is adopted. Many finite element studies have already been proposed to explore bone-implant interface, revealing the benefits of the adapted structure of implants [10], or the advantages of low Young's modulus alloy [23]. The specific scope of dental field is particularly investigated [33][34][35].…”