State of the Art in Directed Energy Deposition: From Additive Manufacturing to Materials Design

Abstract

Additive manufacturing (AM) is a new paradigm for the design and production of high-performance components for aerospace, medical, energy, and automotive applications. This review will exclusively cover directed energy deposition (DED)-AM, with a focus on the deposition of powder-feed based metal and alloy systems. This paper provides a comprehensive review on the classification of DED systems, process variables, process physics, modelling efforts, common defects, mechanical properties of DED parts, and quality control methods. To provide a practical framework to print different materials using DED, a process map using the linear heat input and powder feed rate as variables is constructed. Based on the process map, three different areas that are not optimized for DED are identified. These areas correspond to the formation of a lack of fusion, keyholing, and mixed mode porosity in the printed parts. In the final part of the paper, emerging applications of DED from repairing damaged parts to bulk combinatorial alloys design are discussed. This paper concludes with recommendations for future research in order to transform the technology from “form” to “function,” which can provide significant potential benefits to different industries.

Evolution of 3D Printing Methods and Materials for Electrochemical Energy Storage

“…Nevertheless, porosity is common in these powder bed processes requiring hot isostatic pressing or infilling with another material to improve the mechanical properties of the finished product. [17,18] To fabricate a dense and mechanically stable 3D structures such as active material constructors or current collectors, DED is another powder-or wire-based printing method that utilizes a laser or electron beam focused on a substrate producing a melt pool to which a coaxial powder stream or a wire feed is injected, building a 3D structure [19,20] (Figure 1h). Despite producing robust structures, the process is time consuming and requires inert conditions making it expensive for industrial use.…”

“…Several examples of successful adoption of additive manufacturing in mass production have emerged in recent years. Among others, footwear, automotive parts, and even almost fully printed cars, dental aligners, medical prosthetics, implants, tools, etc., [30,159] parts for aerospace industry, [18,25] electronic devices, [20,38,160] jewelry [40] are all being mass-produced using a variety of additive manufacturing techniques, such as VAT-P, SLM, ME, SLS, aerosol jet printing, etc. Given the ongoing development of new hardware and software with improved specifications, extensive research in 3D printing, and many undeniable benefits of additive manufacturing, it is almost certain that the number of businesses and industries that move toward the adoption of AM will grow rapidly in the near future.…”

Investigation of Micro-Hardness, Wear Resistance, and Defects of 316L Stainless Steel and TiC Composite Coating Fabricated by Laser Engineered Net Shaping

“…Laser engineered net shaping (LENS) is an additive manufacturing technology that is used to manufacture parts with enhanced property by melting a powder and depositing onto substrate with high energy laser beam [1][2][3]. This technology has become an academic and industrial focus because of the exceptional physical property, high density, and low pore rate of the finished product [4,5].…”

Development of Vitroceramic Coatings and Analysis of Their Suitability for Biomedical Applications

“…Finally, the samples biocompatibility was assessed and they were found to be bioactive after simulated body fluid soaking and biocompatible through the MTT cell viability test.Coatings 2019, 9, 671 2 of 13 drawbacks, like fibrous tissue growth, slow osseointegration and reduced close contact with the host bone, were noticed upon wider use of titanium alloy implants [19]. Thus, the quest is to develop a composite material with all the mechanical properties of titanium alloys, encapsulated in a leak-proof ceramic, that can be biologically preactivated prior to implant [20,21].With the advent of laser-based additive manufacturing [22], such composite material is now a reality. In this case, a commercial or custom-made ceramic target is ablated by a pulsed laser, a plume of plasma is generated and directed towards the metallic substrate, upon which it settles, forming a thin layer that physically binds to the support [23,24].…”

“…With the advent of laser-based additive manufacturing [22], such composite material is now a reality. In this case, a commercial or custom-made ceramic target is ablated by a pulsed laser, a plume of plasma is generated and directed towards the metallic substrate, upon which it settles, forming a thin layer that physically binds to the support [23,24].…”