Mo‐based alloys with solidus temperatures around and above 2000 °C are attractive high‐temperature structural materials for future applications in the hot section of gas turbines. However, their oxidation behavior is poor due to pesting starting at 600 °C and nonprotective oxide growth at temperatures above 1000 °C. To ensure a sufficient oxidation resistance over a wide temperature range, protective coatings become inevitable. Herein, silicon coatings have been applied by magnetron sputtering on Mo‐9Si‐8B and on titan–zirconium–molybdenum alloy (TZM). The coating architecture is designed to minimize the intercolumnar gaps and porosity, thereby increasing the density. Specimens are tested at 800 and 1200 °C in air isothermally for up to 300 h. The focus is put on the chemical reactions at the coating–substrate interface, the phase formation, and the evolution of the thermally grown oxide. An initially globular SiO₂ evolves into a uniform SiO₂ layer providing excellent oxidation protection. The investigations reveal a rather slow interdiffusion between the coating and the alloys when tested in air. At the coating–substrate interface exclusively, the Mo₃Si phase develops. Finally, the phase formation at the coating–substrate interface is studied in detail for various heat treatments in air and vacuum.

The implementation of a structural material into the hot section of a turbine engine requires the protection against oxidation and water vapour. Since Mo-Si-based alloys do not provide this protection on their own over a long period of exposure time, the necessity for protective coatings becomes inevitable. Rare earth silicates, especially Yb-silicates, are known for their great potential to protect silica against water vapour recession and also for their oxidation protective behaviour due to their low silica reactivity. Reactive pulsed DC co-sputtering was investigated and used to produce a two-layered coating of Yb₂Si₂O₇ and Yb₂SiO₅. The layers were implemented into a four-layered environmental barrier coating system combined with a bond coat consisting of a graded Mo-Si interlayer and a thin Si top layer intended to form slow-growing silica. The EBCs were tested up to 100 h at 1200 °C and 800 °C isothermally in air on top of three different Mo-Si-based alloys and show promise for oxidation protection. The pesting phenomenon was completely suppressed.

The widespread use of antibiotics worldwide has led to an increase in multi‐resistant pathogens, including vancomycin‐resistant enterococci (VRE). To prevent the spread of multi‐resistant pathogens, antimicrobial surfaces have become more widely used. Various metals and surface topographies are researched to optimize their bactericidal effect. Copper surfaces have proven cost‐effective, easy to implement, and safe. However, concurrent metal resistance in Enterococcus faecium , leads to strains highly resistant to both vancomycin and copper. The efficacy of copper coatings are evaluated, and copper and brass surfaces are functionalized with Direct Laser Interference Patterning (DLIP) and determined the release of copper and zinc ions during cell‐surface. Additionally, the copper stress response of five E. faecium isolates is characterized by scanning and transmission electron microscopy, determination of the minimal inhibitory concentration (MIC) on copper‐infused media, and whole‐genome sequencing. The copper stress responses of the isolates differed due to their different copper resistance genes. In particular, it is shown that prior exposure to vancomycin enhanced copper tolerance in E. faecium . Furthermore, the copper‐tolerant isolate is the only one to survive direct contact with the functionalized copper surface. These results highlight the importance of investigating antimicrobial and functionalized surfaces against hospital pathogens and co‐resistance against metal and antibiotics.

Mechanical properties of three different coatings comprising of pure silicon, 36 mol% HfO2-doped silicon and 60 mol% HfO2-doped silicon on SiC substrate material were obtained by nanoindentation. The coatings aim at oxidation protective layers in environmental barrier coating systems for SiC/SiC ceramic matrix composites (CMC). The examined coatings were produced by physical vapour deposition (magnetron sputtering) and have been tested under cycling conditions between room temperature and 1523 K until 100 h accumulated hot time. In order to measure the hardness and the reduced Young's modulus, a Berkovich tip has been used with a constant depth modulus of 100 nm and 160 nm. Two depth moduli have been chosen to investigate a possible volume impact on the mechanical properties. Six successfully produced indents have been averaged to examine the hardness and reduced Young's modulus. The testing has been done on polished cross sections thereby minimising the impact of the substrate material on the measured values. This article provides data related to “Hafnia-doped Silicon Bond Coats manufactured by PVD for SiC/SiC CMCs”.