The HVOF forming is a process that permits to obtain wear resistant self-standing forms. The self-supporting forms that are obtained through the reshaping process by means of thermal spraying have two free surfaces that do not necessarily have the same structure or the same properties. This paper investigates the mechanical properties of the obtained in relation to the structure. It compares the structure-property relationship of the internal and external surfaces. The results show the anisotropic behavior of the internal and external free surfaces and their difference to the cross section. The structure of the system is characterized in terms of its nature, phase distribution, composition, and porosity. For the mechanical properties, the paper examines the microhardness and the modulus of elasticity of the material. Paper includes a German-language abstract.

The feasibility of using the HVOF process for the thermal spray-forming of free-standing components has been investigated. HVOF spray forming offers a number of potential advantages compared to the established procedure of plasma forming, including increases in component density, and reduction in material decomposition during spraying. Using blends of carbide and superalloy powders in various proportions, HVOF spraying has been successfully used to form free-standing cylinders and cones of various lengths and thicknesses. Microstructural examination of the spray-formed material, using optical microscopy and scanning electron microscopy (SEM), has shown a homogeneous distribution of carbides in the superalloy matrix, with very low levels of porosity. Vickers microhardness has been measured on several sprayed forms. In order to complete the study of the different systems, abrasion (Rubber Wheel Test), friction (Ball on Disk Test) and erosion wear results have been obtained. These wear results have been used in order to evaluate the behaviour of the sprayed samples with a different powder percentage in the blends. Corrosion tests have been done to evaluate the corrosion resistance of the sprayed samples (ASTM D-1411).