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Columnar‐structured thermal barrier coatings (TBCs) manufactured by electron beam‐physical vapor deposition (EB‐PVD) are well known to exhibit high strain tolerance. However, as EB‐PVD is a high‐vacuum process, it is expensive. Suspension plasma spraying (SPS) and plasma spray‐physical vapor deposition (PS‐PVD) are alternatives for the manufacture of similar microstructures. Herein, the state of the art of manufacturing columnar‐structured TBCs by SPS and PS‐PVD is outlined. Both processes have been investigated and further developed at Forschungszentrum Jülich for many years. The mechanisms leading to the formation of columnar‐structured coatings are described and differentiated from EB‐PVD. Examples are given for SPS and PS‐PVD columnar microstructures and their life performance. [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]