Inconel 718 (In718) is the most widely used nickel-based alloy in additive manufacturing due to its favorable processability. However, In718’s high-temperature performance is not suited for the most demanding applications in the aerospace industry. Therefore, in this study, Inconel 718 powder was coated with 3% wt. rhenium (In718-Re) using AM’s in situ alloying capabilities to improve high-temperature properties. The proposed alloy’s mechanical performance was evaluated, focusing on the effects of post-process heat treatment and hot isostatic pressing following the laser-based powder bed fusion of metals (PBF-LB/M) processing. Static tensile tests conducted at room temperature and elevated temperatures (650 °C and 760 °C) demonstrated that the alloy has comparable strength to pure In718 according to ASTM F3055-14a—an ultimate tensile strength of 1247 MPa, yield strength of 909 MPa, and almost 2× higher elongation of 23.8%. Fatigue tests at room temperature indicated a fatigue limit below 400 MPa for 10⁷ cycles. Fractographic analysis revealed that fatigue performance was primarily impacted by a lack of fusion defects inherent to the PBF-LB/M process, highlighting the need for optimized powder preparation and processing parameters to minimize defect formation. While rhenium addition shows limited benefits in Inconel 718, this study underscores the potential of in situ alloying through powder surface modification as a flexible method for incorporating high-melting-point elements into nickel-based alloys for tailored alloy design in additive manufacturing.

The growing antibiotic resistance of microorganisms causing postoperative infections following orthopedic surgeries underscores the urgent need for localized antiseptic and lavage delivery systems to enhance infection control. This study evaluates the in vitro effectiveness of antiseptic and lavage solutions—including polyhexanide, povidone–iodine, low-concentrated hypochlorite, Ringer’s solution, and saline—against Staphylococcus epidermidis, Staphylococcus aureus MRSA, Cutibacterium acnes, Corynebacterium amycolatum, Pseudomonas aeruginosa, and Candida albicans. Using microplate models (Minimum Inhibitory Concentration, Minimum Biofilm Eradication Concentration, and Biofilm-Oriented Antiseptic Test assays), flow-based models (Bioflux system), and surfaces relevant to orthopedic implants (e.g., stainless steel disks/screws, Co-Cr-Mo, Ti-Al-Nb orthopedic alloys, and ultra-high-molecular-weight polyethylene), as well as a bio-nano-cellulose scaffold representing tissue, we assessed the solutions’ activity. The cytotoxicity of the solutions was evaluated using osteoblast and keratinocyte cell lines, with additional in vivo insights gained through the Galleria mellonella larval model. The results show that polyhexanide-based solutions outperformed povidone–iodine in biofilm eradication in most tests applied, particularly on complex surfaces, whereas iodine demonstrated higher cytotoxicity in applied in vitro and in vivo tests. Low-concentration hypochlorite solutions exhibited minimal antibiofilm activity but also showed no cytotoxicity in cell line and G. mellonella larval models. These findings highlight the importance of careful antiseptic selection and rinsing protocols to balance infection control efficacy with tissue compatibility in orthopedic applications.

Despite the significant potential advantages of processing Ti-5Al-5Mo-5V-1Cr-1Fe alloy (Ti-55511) using Electron Beam Melting (PBF-EB/M), when compared to conventional manufacturing technologies, the resulting internal defects are an important characteristic of such additive technologies and can highly decrease mechanical properties. One of the most dangerous defects formed during metal additive manufacturing processes are material discontinuities such as a lack of fusion. Defects of this type, due to their “flat” nature, are difficult to characterize. For cycle-loaded specimens, where the loading force acts perpendicular to the lack-of-fusion plane, defects of this type can significantly reduce fatigue properties. This paper presents the results of research aimed at improving the fatigue properties of Ti55511 alloy by reducing the influence of the lack-of-fusion defect on fatigue damage. The static and fatigue properties of specimens in the as-built state, as well as after hot isostatic pressing (HIP) treatment, were analyzed. The effect of HIP on both the reduction of pores and the degree of sphericity when using the X-ray computed tomography (XCT) system was presented. The change in the microstructure after HIP was analyzed in terms of the change in the size of individual phases, as well as the change in the phase ratio. This paper also contains a fractographic analysis of the samples after tensile and fatigue tests.

The growing antibiotic resistance of microorganisms causing postoperative infections following orthopedic surgeries underscores the urgent need for localized antiseptic and lavage delivery systems to enhance infection control. This study evaluates the in vitro effectiveness of antiseptic and lavage solutions—including polyhexanide, povidone-iodine, low-concentration hypochlorite, Ringer’s solution, and saline—against Staphylococcus epidermidis, Staphylococcus aureus MRSA, Cutibacterium acnes, Corynebacterium amycolatum, Pseudomonas aeruginosa, and Candida albicans. Using microplate models (Minimum Inhibitory Concentration, Minimum Biofilm Eradication Concentration, and Biofilm-Oriented Antiseptic Test assays), flow-based models (Bioflux system), and surfaces relevant to orthopedic implants (e.g., stainless steel disks/screws, Co-Cr-Mo, Ti-Al-Nb orthopedic alloys, and ultra-high molecular weight polyethylene), as well as a bio-nano-cellulose scaffold representing tissue, we assessed solutions activity. The cytotoxicity of the solutions was evaluated using osteoblast and keratinocyte cell lines, with additional in vivo insights gained through the Galleria mellonella larval model. Results show that polyhexanide-based solutions outperformed povidone-iodine in biofilm eradication in most tests applied, particularly on complex surfaces, whereas iodine demonstrated higher cytotoxicity in applied in vitro and in vivo tests. Low-concentration hypochlorite solutions exhibited minimal antibiofilm activity but also showed no cytotoxicity in cell line and G. mellonella larval models. These findings highlight the importance of careful antiseptic selection and rinsing protocols to balance infection control efficacy with tissue compatibility in orthopedic applications.

A year after the first cases, the COVID-19 pandemic continued to put immense pressure on healthcare systems worldwide. With supply chains broken, the only opportunity for hospitals was to turn to unconventional solutions to overcome medical equipment shortages in the shortest possible time. This paper describes the methodology that allows the preparation of medical equipment to be additionally manufactured in keeping with medical requirements. The proposed method focuses on cytotoxicity tests against HaCaT, L929, A549 cell lines, and the assessment of potential antimicrobial properties of materials. The application of the proposed method is shown by the example of an adapter that connects a full mask with widely available DAR filters. The prototyping and fabrication of adapters were conducted with the fused deposition modelling (FDM) and selective laser sintering (SLS) technologies. The adapters increased the number of masks available to medical personnel, and by the same token, ensured the continuity of their work.