The DLC Coating on 316L Stainless Steel Stochastic Voronoi Tessellation Structures Obtained by Binder Jetting Additive Manufacturing for Potential Biomedical Applications

Abstract

The DLC coating of samples produced by additive manufacturing with complex shapes is a challenge but also shows the possibility of obtaining a diffusive barrier for biomedical applications. In this study, stochastic porous structures based on Voronoi tessellation were fabricated using binder jetting technology from 316L SS powder and modified using DLC coating. The DLC coating was deposited using the RF PACVD technology. The chamber pressure was 40 Pa with a methane gas flow rate of 60 sccm. The negative bias voltage was 700 V. The deposition time was 5 min. Dimensional analysis was performed using optical microscopy. Surface morphology and topography were evaluated using SEM and confocal microscopy. Raman spectroscopy was used to examine the chemical structure of DLC coating. Finally, the HR TEM was used to evaluate the physicochemical characterization of the DLC coating. The interconnected complex spatial network of the Voronoi structure was accurately duplicated by the binder jetting technology. The obtained substrates were characterized by high roughness (Ra = 6.43 µm). Moreover, the results indicated that the conditions of the RF PACVD process allow for the deposition of the continuous and tightened DLC coating with a thickness from 30 nm to 230 nm and defined the content of Cr2O3 and SiO2.

Surface Modification and Functionalities for Titanium Dental Implants

“…19 Due to the best biocompatibility, matching mechanical properties, and good corrosion resistance, Ti alloys are recognized as the most suitable implant material. 11,20 Various types of Ti implants are widely used in clinical medical restoration. Figure 2A-G illustrates the application of Ti implants in various human tissues, including skull, 21,22 dental implant, 23−25 joint replacement, 26,27 bone scaffold, 28 knee, 29 and stent.…”

“…Biomedical implants are great creations in human medical history, which are widely used to save countless people from the pain of tissue loss and necrosis, especially in the restoration of hard tissues. − The application of suitable materials with good biocompatibility, matching mechanical properties, and stability is the key to developing implants. − To data, there are three typical implants in clinical applications, including stainless steel, cobalt–chromium alloy, and Ti based alloy. − As shown in Figure , the mechanical properties of medical stainless steel are quite different from those of hard tissue, making it is easy to cause implant failure. − Cobalt-based medical metal materials have excellent mechanical properties, wear resistance, and corrosion resistance, but the release of cobalt, nickel, and other metal ions in the constituent elements easily causes cell and tissue necrosis . Due to the best biocompatibility, matching mechanical properties, and good corrosion resistance, Ti alloys are recognized as the most suitable implant material. , …”

Nuevas tecnologías de tratamiento dúplex para la mejora de la adherencia de recubrimientos DLC sobre acero inoxidable austenítico

“…Desde principios de la década de 1990 los recubrimientos DLC han suscitado un gran interés en la industria por sus propiedades físicas (ópticas y eléctricas), químicas (interacción con los medios), mecánicas (dureza, modulo elástico), biomédicas (biocompatibilidad, residuos inertes) y tribológicas excepcionales [52,65,[136][137][138][139][140][141][142][143].…”

“…El sustrato elegido en este estudio es el acero inoxidable austenítico AISI 316L (también denominado 1.4404) empleado por sus propiedades (tabla 10) en la industria aeronáutica, aeroespacial y la industria médica, en especial la protésica debido a sus propiedades biocompatibles [8,42,101,[202][203][204]. Debido al auge de la fabricación aditiva en los métodos de producción industriales se estudiará a su vez las propiedades del recubrimiento dúplex sobre sustratos producidos tanto por fundición como por SLM [143,205]. En el caso de las muestras aditivas todas partieron de la misma secuencia de impresión por lo que los parámetros empleados son iguales y las condiciones de fabricación/fundición se consideran las mismas.…”