Additive Manufacturing: An Opportunity for the Fabrication of Near-Net-Shape NiTi Implants

Abstract

Nickel–titanium (NiTi) is a shape-memory alloy, a type of material whose name is derived from its ability to recover its original shape upon heating to a certain temperature. NiTi falls under the umbrella of metallic materials, offering high superelasticity, acceptable corrosion resistance, a relatively low elastic modulus, and desirable biocompatibility. There are several challenges regarding the processing and machinability of NiTi, originating from its high ductility and reactivity. Additive manufacturing (AM), commonly known as 3D printing, is a promising candidate for solving problems in the fabrication of near-net-shape NiTi biomaterials with controlled porosity. Powder-bed fusion and directed energy deposition are AM approaches employed to produce synthetic NiTi implants. A short summary of the principles and the pros and cons of these approaches is provided. The influence of the operating parameters, which can change the microstructural features, including the porosity content and orientation of the crystals, on the mechanical properties is addressed. Surface-modification techniques are recommended for suppressing the Ni ion leaching from the surface of AM-fabricated NiTi, which is a technical challenge faced by the long-term in vivo application of NiTi.

Manufacturing Technologies of Polymer Composites—A Review

“…Therefore, the establishment of a finite element numerical simulation model can effectively and accurately describe the product manufacturing process at a relatively low cost. Some studies have analysed defects from the manufacturing process of polymer composites by surface coating, additive manufacturing and magnetic pulse powder compaction technology to predict the evolution of defects during the manufacturing process [ 145 , 146 ]. In this paper, the manufacturing process of polymer composites is sorted out, as shown in Table 6 , summarising the technical methods used by previous researchers at the polymer composite manufacturing research institute.…”

Three-dimensional printing as a cutting-edge, versatile and personalizable vascular stent manufacturing procedure: Toward tailor-made medical devices

“…Even if much remains to be done, especially when it comes to 3D-printed VS, it is clear that SMP offer attractive features, from their self-expanding property to the biocompatibility, biodegradability and drug-eluting features, not to mention the possibility of being compatible with different 3DP techniques. The range of future possibilities is even greater if we consider SMP functionalization, surface modifications or their use as part of nanocomposites [ 106, 136 ] .…”

Mechanical Properties and Biocompatibility of 3D Printing Acrylic Material with Bioactive Components

“…In materials that have a longer contact with the patient, a very important parameter is their biological compatibility (it must not be cytotoxic, irritating, or allergic) [ 11 ]. However, polymerization during 3D printing causes only a partial reaction of the double bonds and a certain degree of conversion of the C=C double bonds in the methacrylic group.…”