The German Army is using the Sikorsky helicopter Typ CH-53 G in the marine version, this means that the tail with the rear rotor can be folded sidewise in order to safe space during storage. During flight the fuselage is locked by two gear racks that slide in the bore hole of an aluminium housing. Due to the high friction during the movement of the steel racks the inner bore surface is damaged of up to 1 mm depth. In this paper the repair of this inner surface of the bore by arc-wire spraying is described. A special gun extension was developed so that the narrow bore (diameter 48 mm; length 400 mm) can be repaired. Preliminary test results with various materials are presented. Paper text in German.

In the automotive industry, efforts to lower the cost of manufacturing and reduce the weight of an automobile are an ongoing process. Plasma spraying of cylinder bores on engine blocks made of light cast alloys has been developed over the five years. This paper provides an overview of the actual situation of the technology for coating cylinder bores, from cast material to non-destructive testing. The aspects of both finishing using honing technology and testing are to be seen as an important part of plasma spray technology for cylinder bores. The paper discusses the results of laboratory and field tests in Europe, Japan, and the United States. This shows that the plasma spraying process is a proven and cost-effective solution for coating cylinder bores. The launch aspect is also discussed. Paper includes a German-language abstract.

Atmospheric Rheo-Spraying (ARS) using the HVOF process enables injection-molded structures and thick-film coatings from steels and from high-temperature Ni-based alloys with layer thicknesses down to the centimeter. The ARS process control is based on the thermal spraying of particles in the solid state at a maximum average speed of more than 600 m/s. The coating consolidation to porosity values below 1% occurs through the particle impact with high kinetic energy. Because of the low particle oxidation, the mechanical properties of the heat-treated injection-molded structures are comparable to those of forged alloys. In this paper, ARS injection molding is successfully implemented in combination with an innovative manufacturing technique in rocket engine technology to produce a model composite combustion chamber with a thermally sprayed internal pressure jacket. Paper includes a German-language abstract.

This paper investigates the stability of molybdenum base silicides, which are located in combustion chambers and in an endothermic environment, for use in radiant tubes for heat treatment. The subject matter was plasma-sprayed molybdenum disilicide, pentamolybdenum trisilicide, hot-pressed molybdenum disilicide, and molybdenum disilicide composites containing SiC and silicon nitride reinforcements. Results of the investigation show that the oxidation resistance of plasma sprayed molybdenum disilicide can be detrimentally effected due to the silicon loss that occurs during the high temperature plasma spray process. Paper includes a German-language abstract.