Abstract This paper provides a short summary of the different concepts related to the structure and preparation of titanium carbide (TiC)-containing wettable powders that could be found in the literature. Empirical composite developments of TiC-containing materials for coating applications are not suitable for fully describing the technical potential of these composites. TiC-containing layers can complete the range of thermal coating solutions based on tungsten carbide and chromium carbide. The development of TiC-based powders that are better than the prior state of the art is the result of a long-term process producing permanent improvements. The processability of different TiC-based powders from alloying steps one and two was tested with various high velocity oxygen fuel installations and different fuel gases. TiC-based coatings offer special advantages through tailoring of the composition to suit requirements in applications in which complex stress profiles exist. Paper includes a German-language abstract.

Abstract Molybdenum silicides have the potential as protective coatings for high-temperature applications because of their high melting point and their high-temperature oxidation resistance. Reinforcing MoSi2 with SiC shows an improvement of its low toughness at room temperature and low creep resistance at temperatures above the brittle-ductile transition temperature of approximately 700-1000 °C. A new kind of powder processing was used to produce MoSi2 and MoSi2-SiC as a feedstock for thermal spraying. Mixtures of the elemental powders, molybdenum and silicon, were prepared by milling and subsequent heat treatment to get highly dispersed, pre-reacted powders. As high-energy milling equipment, a planetary ball mill was used to prepare the powders. In the case of reinforcement, SiC was mixed to the pre-reacted MoSi2 at the end of the milling process, that means before heat treatment. On these as-milled powders, X-ray diffraction characterization (XRD), scanning electron microscopy (SEM), electron probe micro analysis (EPMA) and determination of the oxygen level were carried out. Vacuum plasma spraying has been used to deposit the powders onto a carbon steel substrate. Evaluated coating characteristics were the microstructure (SEM), phases (XRD), EPMA, oxygen content, microhardness and surface roughness. Tests at high temperatures will be considered in future work.