The electrolyte supported cells with low area specific resistance (ASR<0.34 Ohm cm²) have been tested for long-term, thermal and redox stability in ceramic housing. It has been shown that the cells with optimized anode microstructure have degradation <0,1 % / 1000h and no measurable resistance change in the range of mistake of used method after ten thermal and redox cycles. The small fluctuation of contact resistance between anode and current collector has been observed especially during cycling experiments. The redox cycles lead to the largest fluctuation of ASR values during cycling due to direct influence on the bonds between anode and current collector.

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Printed magnetic field sensors enable a new generation of human-machine interfaces and contactless switches for resource-efficient printed interactive electronics. As printed magnetoresistors rely on scarce or hard to manufacture magnetosensitive powders, their scalability and demonstration of printing with industry-grade technologies are the key material science challenges. Here, the authors report dispenser printing of a commodity scale nonmagnetic bismuth-based paste processed by large area laser sintering to obtain printed magnetoresistive sensors. The sensors are printed on different substrates including ceramics, paper, and polymer foils. It is validated experimentally that the peculiar quantum large orbital magnetoresistive effect remains effective in printed bismuth sensors, allowing their operation in high magnetic fields. The sensors reveal up to 146% resistance change at 5 T at room temperature with a maximum resolution of 2.8 μT. If printed on flexible foils, these sensors show resilience to bending deformation for more than 2000 bending cycles and withstand even thermal forming, as relevant for smart wearables and in-mold electronics. The freedom in the substrate choice and sensor design enabled by dispenser printing allows to implement the proposed sensor technology for different applications focused on touchless interactive platforms, such as advertisement materials, interactive wallpapers, and printed security panels.

The electrolyte supported cells satisfy the requirements for the application in the solid oxide fuel cell such as mechanical stability, long-term stability during operation at temperatures <1000{degree sign}C, thermal cycling and very low degradation during repeated anode reduction/oxidation cycles. Nevertheless an enhancement of the power density at T=800-850{degree sign}C should be achieved to increase the power density level towards anode supported cells. The electrolyte supported solid oxide fuel cells on dense 8YSZ or 10Sc1CeSZ tapes (50x50x0.150 mm) with screen printed nickel oxide and yttria stabilized zirconia cermet anode (NiO/YSZ) and lanthanum strontium manganite and yttria stabilized zirconia composite cathode (uLSM/YSZ) were sintered in co-firing. The long-term tests (over 1000 hours) were carried out at 850{degree sign}C at constant load of 550 mA/cm2 (H2:H2O:N2=40:5:55, fuel utilization uf=50%) for 8YSZ based MEA and 650 mA/cm2 (H2:H2O=50:50, uf=23%) for 10Sc1CeSZ based MEA. During the redox cycle the cells were unloaded and fully oxidized by air for 120-180 min. Up to 10 redox cycles were performed. The field emission scanning electron microscopy (FESEM) was used to characterize the microstructural changes that occurred after long-term and redox cycles experiments. Changes of polarization resistance of the cells during the experiments were analyzed by impedance spectroscopy.

Reactive air brazing (RAB) is a cost‐effective way to produce ceramic–ceramic or ceramic–metal brazed joints in air, without applying a protective gas atmosphere or a vacuum. In addition to conventional furnace technology, the brazing with induction heating can also be used effectively. Within the scope of this study the shrinkage and wetting behavior of self‐developed brazing pastes with different CuO contents and two qualities of silver powders with coarse and fine particle size are investigated by optical dilatometry on alumina (Al2O3, 99.7% purity). Thereby, the fine silver powder quality reveals a significant swelling effect at high temperatures, leading to an expansion of densified powder compacts caused by evolving gases. Joining tests are performed on ceramic–steel brazed joints using a muffle furnace and induction heating for short brazing cycles. The brazing seams and interfaces of the joints are investigated using scanning electron microscopy (SEM) and energy‐dispersive X‐ray spectroscopy (EDS). As a result, correlations between the brazing filler metal composition, the steel, and the brazing conditions are obtained.