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Understanding mechanisms behind the formation and propagation of ionisation zones, so-called spokes, have been highly important since the first observations in high power impulse magnetron sputtering discharges. To this day, however, a complete description is still lacking. This contribution gives an insight into the spokes in reactive Ar–N2 atmosphere using titanium target. The aim of this study is to describe not only global parameters of spokes such as their shape, length and propagation velocity but also provide a description of parameters evolving over the spoke, such as floating potential and spectral emission. The measurements of the latter clearly showed which species emission is most prominent and how it changes with transition from non-reactive argon discharge towards the discharge driven in a pure nitrogen atmosphere. Implications on the gas dynamics and discharge transitions are discussed.

Ta&ndash, B&ndash, C coatings were non-reactively sputter-deposited in an industrial batch coater from a single segmented rotating cylindrical cathode employing a combinatorial approach. The chemical composition, morphology, microstructure, mechanical properties, and fracture resistance of the coatings were investigated. Their mechanical properties were linked to their microstructure and phase composition. Coatings placed stationary in front of the racetrack of the target and those performing a 1-axis rotation around the substrate carousel are compared. Utilization of the substrate rotation has no significant effect on the chemical composition of the coatings deposited at the same position compared to the cathode. Whereas the morphology of coatings with corresponding chemical composition is similar for stationary as well as rotating samples, the rotating coatings exhibit a distinct multilayered structure with a repetition period in the range of nanometers despite utilizing a non-reactive process and a single sputter source. All the coatings are either amorphous, nanocomposite or nanocrystalline depending on their chemical composition. The presence of TaC, TaB, and/or TaB2 phases is identified. The crystallite size is typically less than 5 nm. The highest hardness of the coatings is associated with the presence of larger grains in a nanocomposite structure or formation of polycrystalline coatings. The number, density, and length of cracks observed after high-load indentation is on par with current optimized commercially available protective coatings.

The industrial production of high manganese steel melts with approx. 10–30 wt% Mn makes high demands on the utilized Mn-bearing alloying agents in terms of chemical composition and cost-efficiency. Conventional Mn-bearing alloying agents are reviewed in this regard. A modified process route has been conceived for pyrometallurgical winning of special silicomanganese grades tailored for high manganese steelmaking. For each individual process step, namely manganese slag production, silicomanganese production, and optional desiliconization of silicomanganese, results of lab-scale experiments are discussed.

Multilayered coatings are routinely obtained in non-reactive processes employing multiple sources or in processes with a reactive gas. W-B-C coatings were sputter deposited in an industrial sputtering system in a non-reactive atmosphere onto substrates performing one- and two-axis rotations around a central cylindrical target composed of boron-carbide, tungsten and graphite ring-shaped segments. This study describes the unexpected multilayered structure of W-B-C coatings deposited by even the non-reactive sputtering of a single target. This multilayered structure exhibits a modulation of the chemical composition. While the tungsten content in a layer decreases, the amount of boron and carbon rises. The modulation period corresponds with the calculated thickness increment per one sample revolution around the central cathode. Experiments proved that the chemical composition of a coating and its deposition rate are very sensitive to the substrate position in the chamber. This was attributed to the different transport pathways of heavy (W) and light (C and B) atoms sputtered from the same target, but differently scattered by the working argon gas.