3D thixo-printing: A novel approach for additive manufacturing of biodegradable Mg-Zn alloys. (November 2020)

• Record Type: Journal Article
• Authors: Lima, Dalton Daniel; Campo, Kaio Niitsu; Button, Sergio Tonini; Caram, Rubens
• Is Part Of: Materials & design. Volume 196(2020)
• Publication Date: 2020-11
• Subjects: Mg-Zn alloys -- Biomaterial -- Biodegradable materials -- Fused deposition modeling -- Semi-solid printing -- 3D Thixo-printing; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2020.109161
• Languages: English
• ISSNs: 0264-1275

Abstract

Abstract: A simple and widely used additive manufacturing technique for polymeric materials is fused filament fabrication (FFF). In the semi-solid state, metallic materials may show rheological features comparable to those of polymers. Thus, they can be processed accordingly. The use of biodegradable Mg-based materials is an interesting approach to avoid removal surgeries and release of toxic corrosion products and wear debris. Therefore, in this study, the FFF technique was applied using a biodegradable Mg-Zn alloy in the semi-solid state. Some preliminary compositions were investigated through thermodynamic simulations to verify their compatibility with the process. Among them, Mg-38Zn was selected to be experimentally evaluated. Metallic filaments were produced via hot extrusion, which also aided in obtaining a globular microstructure in the semi-solid state. FFF was performed at 420 °C without any obstruction at the nozzle channel, which allowed the production of sound parts with acceptable welding between the deposited layers. This indicated that this technique (termed as "3D thixo-printing") provides a promising additive manufacturing route to produce biodegradable Mg-based implants. Graphical abstract: Unlabelled Image Highlights: Investigation of an additive manufacturing method for semi-solid Mg-Zn alloys (Mg-xZn, x = 30 - 45 wt. %). Simulations and thermal analysis suggested that Mg-38Zn is a promising composition for semi-solid applications. Successful printing of biodegradable Mg-38Zn was carried out at 420 °C, resulting in fine and globular microstructures.