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Spark plasma sintering as the prominent field‐assisted sintering technique (FAST/SPS) is a novel technology for the rapid, pressure‐assisted consolidation of powder materials. The main feature of FAST/SPS is the direct Joule heating of the applied tooling. Tooling is a challenging part of the FAST/SPS setup, which must withstand high pressure at elevated temperatures and ensure a uniform temperature distribution in the sintered part. This review looks at the standard FAST/SPS tooling, the specific tooling for sintering complex‐shaped parts, and for pressureless sintering. A particular focus lies on graphite, the commonly used tooling material, and on alternative materials such as steel, alloys, ceramics, and composites. The review also considers the add‐on tooling elements, such as spacers, foils, and thermal insulation. Furthermore, the article discusses the basics of FAST/SPS modeling, and the computer‐based optimization of FAST/SPS tooling, the procedure used, and the modeling accuracy. The review briefly describes the tooling and equipment for manufacturing upsized parts and large‐scale production. In addition, the article considers the tooling for FAST/SPS sintering under high pressure (up to 1 GPa) and ultra‐high pressure (over 1 GPa). The article concludes with an analysis of the challenges and prospectives for the smart design of FAST/SPS tooling. [ABSTRACT FROM AUTHOR]

In high‐temperature combustion atmospheres, well‐adhering environmental barrier coatings (EBCs) are required to protect the underlying ceramic matrix composites (CMCs) from corrosion. Herein the adhesion mechanisms of three different coatings produced by atmospheric plasma spraying (APS) on an Al2O3/Al2O3‐CMC are investigated. In particular, the influence of surface structuring by laser ablation prior to coating production is investigated. Y2O3, yttria‐stabilized zirconia (YSZ), and Gd2Zr2O7 are chosen as potential EBCs. The coating adhesion on CMC‐substrates with and without surface structuring is analyzed by furnace cycling, pull‐adhesion tests, and burner‐rig tests with gradient. Special interest is paid to the interactions at the coating–substrate interface before and after heat treatment and their effect on the coating adhesion and lifetime. Two different adhesion mechanisms are found: adhesion promoted by chemical reaction and adhesion promoted by mechanical interlocking. [ABSTRACT FROM AUTHOR]

Aiming toward an optimization of dual phase oxygen transport membrane materials for oxygen separation applications, ceramic composites consisting of a Ce1−xGdxO2−δ (0 < x < 0.2) fluorite phase, Gd0.9Ce0.1Fe0.8Co0.2O3 perovskite phase, FexCo3−xO4 (0 < x < 1) spinel phase, and CoO rock salt phase are developed and micromechanical properties (elastic modulus and hardness) of xCe0.8Gd0.2O2−δ: (1−x)FeCo2O4 (50 wt% ≤ x ≤ 90 wt%) composites are characterized via indentation testing at room temperature. The results obtained at low indentation loads indicate that the magnitude of the elastic moduli of the different phases is in the order Gd0.9Ce0.1Fe0.8Co0.2O3 > Ce1−xGdxO2−δ ≈ FexCo3−xO4 > CoO, and furthermore, hardness values are also in the same order. The hardness values of the obtained composites at higher impression loads reveal a stronger dependency on porosity than on composition due to similar hardness values of the main phases. Any compositional effect appears to diminish above a porosity of ≈1%. [ABSTRACT FROM AUTHOR]

Gas turbine components are often operated in harsh conditions, which can lead to severe damage. As it is highly desirable from both an economical and an ecological point of view to restore these worn areas instead of manufacturing new components, repair technologies are of huge interest for companies supplying maintenance and overhaul of gas turbines. In this article, two thermal techniques are described that can be used for this application: cold gas spraying (CGS) and vacuum plasma spraying (VPS). The CGS process allows the deposition of metallic coatings with excellent mechanical properties; several examples including γ‐TiAl, Inconel (IN) 718, and IN 738 are given. Essential for the deposition of high‐performance coatings in CGS is to exceed the so‐called critical velocity. This is discussed also with experimental findings. As a final topic, experiments that use VPS for the repair of single‐crystal alloys are described. [ABSTRACT FROM AUTHOR]

A radical and rapid transformation of the energy and transportation sectors is required on a global scale in order to stop the massive greenhouse gas emissions which have been modifying our planet at an alarming pace. The contributions to research and development made by the Institute of Energy and Climate Research (IEK) thus include energy conversion and storage technologies as well as the mechanisms of climate change. Jülich scientists develop and optimize electrochemical storage systems such as batteries, fuel cells, electrolyzers and further Power-to-X technologies. [Extracted from the article]