Wire arc additive manufacturing (WAAM) is an emerging and promising technology for producing medium-to-large-scale metallic components/structures for different industries, i.e., aerospace, automotive, shipbuilding, etc. It is now a feasible alternative to traditional manufacturing processes due to its shorter lead time, low material waste, and cost-effectiveness. WAAM has been widely used to produce components using different materials, including copper-based alloy wires, in the past decades. This review paper highlights the critical aspects of WAAM process in terms of technology, various challenges faced during WAAM process, different in-process and post-process operations, process monitoring methods, various gases, and different types of materials used in WAAM process. Furthermore, it briefly overviews recent developments in depositing different copper-based alloys via WAAM process.

Additive manufacturing of Nitinol is a promising field, as it can circumvent the challenges associated with its conventional production processes and unlock unique advantages. However, the accompanying surface features such as powder adhesions, spatters, ballings, or oxide discolorations are undesirable in engineering applications and therefore must be removed. Plasma electrolytic polishing (PeP) might prove to be a suitable finishing process for this purpose, but the effects of post-processing on the mechanical and functional material properties of additively manufactured Nitinol are still largely unresearched. This study seeks to address this issue. The changes on and in the part caused by PeP with processing times between 2 and 20 min are investigated using Nitinol compression springs manufactured by Laser Beam Melting. As a benchmark for the scanning electron microscope images, the differential scanning calorimetry (DSC) measurements, and the mechanical load test cycles, conventionally fabricated Nitinol springs of identical geometry with a medical grade polished surface are used. After 5 min of PeP, a glossy surface free of powder adhesion is achieved, which is increasingly levelled by further polishing. The shape memory properties of the material are retained without a shift in the transformation temperatures being detectable. The decreasing spring rate is primarily attributable to a reduction in the effective wire diameter. Consequently, PeP has proven to be an applicable and effective post-processing method for additively manufactured Nitinol.

A novel, environmentally friendly, fast, and flexible polishing process for Nitinol parts is presented in this study. Nitinol samples with both superelastic and shape memory properties at room temperature were investigated. The chemical contamination and surface roughness of superelastic Nitinol plates were examined before and after plasma electrolytic polishing. The shift in phase transformation temperature and tensile strength before and after the polishing process were analysed using Nitinol wire with shape memory properties. The obtained experimental results were compared to the data obtained on reference samples examined in the as-received condition. It was found that plasma electrolytic polishing, when the right process parameters are applied, is capable of delivering Nitinol parts with extremely high surface quality. Moreover, it was experimentally proven that plasma electrolytic polishing does not have a negative impact on functionality or mechanical properties of polished parts.

In many cases, the functional performance of additively manufactured components can only be ensured by finishing the functional surfaces. Various methods are available for this purpose. This paper presents a procedure for selecting suitable processes for finishing laser beam melting additive–manufactured parts which is ultimately based on technological knowledge. It was experimentally proven that the use of several consecutive finishing processes is beneficial to achieve better surface quality. One finishing process chain was particularly effective (namely particle blasting/vibratory grinding/plasma electrolytic polishing) and the technological limits of this method were investigated in this study. The optimal parameters for this process combination ensured a surface roughness S_a < 1 µm.

The sustainable development of products is of great interest to both industry and consumers due to various factors, such as anthropogenic climate change and the scarcity of resources and materials. In response to this, the simul⁺ Living Lab Sustainable Additive Manufacturing in Saxony (SAMSax) has been established as a physical experimental space aimed at improving the sustainability of products. This includes selecting resource-efficient manufacturing processes, using renewable materials, reducing energy consumption during use, and designing for recyclability. The innovative approach of the lab also integrates an open innovation process, involving present and potential stakeholders. Collaborating closely with stakeholders from industry, academia, and government fosters idea generation, provides solution approaches, and enhances acceptance and practical implementation. Methodologically, SAMSax focuses on upcycling organic and inorganic residues as well as by-products from industry and agriculture, reintegrating them as innovative components in industrial production using additive manufacturing (“3D printing”). The Living Lab provides a space for networking and active knowledge transfer through digital technologies, analyses, and collaborative developments, enabling the testing and evaluation of innovations in a real-world environment. Several potential waste materials suitable for additive manufacturing and new products have already been identified. In addition to industrial residues, materials, such as paper and wood dust; industrial by-products, such as sand; and agricultural residues, like harvest residues, are being analyzed, processed, and tested using additive manufacturing in the laboratory. In this way, SAMSax can contribute to an integrated and consistent circular economy. The research aims to demonstrate that the SAMSax Living Lab is a crucial driver of innovation in the field of additive manufacturing. Furthermore, this study contributes by presenting the Living Lab as an application-oriented research environment, focusing on innovative implementation in small- and medium-sized enterprises.