High Energy Ball Milling Prepared Al₂O₃-NiCr Dispersion Powders for Thermal Spray Coatings

This work concerns the production and use of aluminum oxide-NiCr dispersion powders for thermal spraying. It investigates the morphology and hardness of the powders and the microstructure and wear resistance of the resulting coatings. The powders are prepared by high energy ball milling and are used to produce oxide dispersion strengthened NiCr coatings via HVOF spraying. Among the key findings is that the powders are less homogeneous when milled with nanoscale aluminum oxide as are coating properties. Paper includes a German-language abstract.