# Advanced Manufacturing Processes
## 2 Overview of Published Articles  
The present Special Issue encompasses 11 original research papers, each addressing different areas of manufacturing technology. Specifically, four-papers address material welding and joining, five papers are focused on subtractive manufacturing (machining/cutting processes), one paper addresses material forming, and one paper focuses on dimensional control in assembly. Different research topics and different methodological approaches have been studied/followed among the works published in this Special Issue, highlighting its multidisciplinary nature. The works addressing welding and joining processes encompass studies on solid-state welding techniques, like friction welding, friction stir welding and magnetic pulse welding, and fusion welding techniques, specifically laser welding. It is important to stress that all of these works address the joining of dissimilar materials with very different chemical, physical, and mechanical properties. Regarding the study on friction welding, [PERSON] et al. (Contribution 1) used this technique to produce dissimilar welds of tungsten-heavy alloy and 5 XXX aluminum alloy. The research approach followed by these authors was based on experimental and finite-element results. A good correlation between the experimental and the numerical results was found in terms of the weld geometric characteristics and temperature. The maximum weld temperature was found to be 581 \({}^{\circ}\)C, which was slightly higher than the temperature measured during the experimentation. Theflash width, flash height, and axial weld shortening were predicted with small deviation values, which ranged between 2.34% and 4.45%. Also using a friction-based welding technique, [PERSON] et al. (Contribution 2) addressed the dissimilar friction stir welding of aluminum and magnesium. These authors explored the influence of tool rotation speed on the formation of eutectic structures during the friction stir welding of aluminum to magnesium in order to avoid liquation and solidification problems. Through many characterization techniques, they found that changing the rotation speed directly affected the eutectic formation, whereas the welding speed did not present any influence. A lower rotation speed during the process resulted in a thin, continuous intermetallic layer, whereas a higher speed led to the formation of a massive Mg-Al\({}_{12}\)Mg\({}_{17}\) eutectic microstructure. The formation of a eutectic mixture, as indicative of liquation, may affect the material flow during the process due to the decreased friction coefficient between the tool and material. Similar to the previous two works, a solid-state welding technique was also studied by [PERSON] and [PERSON] (Contribution 3). However, in order to produce Al/steel joints, these authors used an impact-based technique, i.e., magnetic pulse welding. In fact, according to these authors, the use of evolutionary algorithms to reach optimal process parameters in magnetic pulse welding has been poorly explored in the literature. This way, their work was dedicated to maximizing the quality of Al/steel magnetic-pulsed (MP) welds by using evolutionary algorithms, i.e., an Imperialist Competitive Algorithm (ICA) and a Genetic Algorithm (GA). Prediction models were developed; the peak current, gap between workpieces, and frequency were selected as the input parameters; and the maximum load and weld length were selected as the output parameters. Their results showed a good agreement between the predicted values and experimental results for the maximum load and weld length, mainly when the ICA-based model was used. Unlike the welding works described above, [PERSON] et al. (Contribution 4) worked on fusion welding--in particular, on laser direct joining. Specifically, they studied the influence of temperature distribution on the interfacial bonding process between carbon-fiber-reinforced thermoplastic (CFRTP) composites and 6061 aluminum alloy during laser direct joining.