For the past 19 years, high entropy alloys (denoted as HEAs) have piqued the interest of many researchers due to their unique properties. Sputtering High Entropy Alloys on bulk materials, on the other hand, have been widely utilized due to their low cost of manufacture. This paper reviews the most recent trends and advancements in sputtered HEA coatings, thin film research, and development. Firstly, HEA coating and thin films were introduced. Then, a look at sputtering technologies and procedures is presented, followed by a summary of recent research on sputtered HEA thin films, properties, and applications. From reviewed literature, it can be deduced that HEAs that include the full nitride element have greater mechanical and elastic properties, and HEAs generally have the potential for structural, industrial, biomedical, and energy applications. Finally, it is suggested that new stable HEA films and coating research initiatives with various materials be undertaken to widen its applications.

Despite its well-reported application in a few welding processes, the use of reinforcing powders in weld joints to improve weld integrity has not garnered ample research attention for Gas Metal Arc Welding (GMAW) process. In this study, the adoption of Titanium alloy powders as metallic reinforcement for mild steel butt welds was investigated. By adopting Taguchi’s L4 orthogonal array, process optimisation for titanium-reinforced mild steel butt welds were first carried out. In the second phase of welding, the optimum parameters were used to create and compare two sets of weldments; one set was reinforced with titanium alloy powder and the other set left unreinforced. It was observed that in the Weld Metal (WM) region, the titanium-reinforced samples had higher micro-hardness values than their unreinforced counterparts with an average of 285.62 HV and 211.6 HV respectively. However, there was no substantial improvement in the ultimate tensile strength of the mild steel butt welds due to titanium powder reinforcements. Interestingly, the formation of acicular ferrite microstructure was more prevalent in the titanium-reinforced weldments and this was attributed to the presence of titanium inclusions in the weld metal. This prevalence of acicular ferrite suggests improved toughness properties in the weld joint region. While the higher hardness values in the Weld Metal of the reinforced sample indicates improved wear resistance.