This paper presents a process for manufacturing parts using HVOF spraying techniques. The parts are made from a mixture of chromium carbide and nickel chromium alloy powders and are characterized based on microstructure, hardness, and corrosion and wear performance. Paper includes a German-language abstract.

The growing use of thermal spray technology in manufacturing is increasing the need for knowledge regarding the behavior of thermal spray coatings in aggressive environments. Due to the different characteristics of the spraying processes and materials used, the mechanisms of attack can vary greatly from layer to layer depending on the application. This paper presents a detailed investigation of corrosion mechanisms at room temperature and their effect on a wide range of thermally sprayed metals and ceramic-metal (cermet) composites. Paper includes a German-language abstract.

A number of experiments were carried out to optimize the thermal spraying of stainless steel using online monitoring. The experiments were designed to determine the influence of spraying conditions on in-flight particle behavior and layer properties. By measuring the speed, temperature, and spatial distribution of the particle stream, the monitoring system made it possible to optimize spray parameters and thus produce stainless steel layers with tailor-made properties. Paper includes a German-language abstract.

In this study, polyamide 11 and polyamide-alumina layers are produced by flame spraying and assessed based on microstructure and corrosion and wear resistance. Among the more notable findings: During the spraying process, there is a loss of crystallinity and polymorphism in the polymer due to high heating and cooling rates. Although some particle degradation occurs in flight, it is does not significantly alter the properties of the polymer. Insufficient substrate temperature impedes the melting of the polymer matrix and embedding of the ceramic filler particles, which has a negative effect on the abrasive wear resistance of the resulting composite layer. Overall, the coatings exhibit good corrosion resistance. During electrochemical testing in a saline solution, there was no electrolyte penetration. Paper includes a German-language abstract.

Thermal spray coatings as Cr 3 C 2 -NiCr obtained by high velocity oxy-fuel spraying (HVOF) are mainly applied due to their behaviour against aggressive erosive-abrasive and corrosive atmospheres and their thermal stability at high temperatures. In order to increase the corrosion protection that it offers to the substrate trying to close the interconnected pores, it is possible to apply a thermal treatment with the gun during the spraying of the coating. This treatment could be applied in different ways. One of these ways consists of spraying only a few layers of coating followed by thermal treatment and finally the spray of the rest of layers. This thermal treatment on spraying is studied related to the corrosion properties of the system. The study comprises the electrochemical characterisation of the system by open circuit potential (OC), polarisation resistance (R p ), cyclic voltammetry (CV) and impedance spectroscopy measurements (EIS). Optical and scanning electron microscopy characterisation (OM and SEM) of the top and cross-section of the system has been used in order to justify the electrochemical results.

This paper presents the electrochemical characterization of a chromium carbide-NiCr coating applied using high-speed flame spraying. It examines the behavior of the complete system, the steel, the steel coating, and the coating immersed in NaCl solution alone. The paper discusses electrochemical measurement methods such as the measurement of polarization resistance, anodic polarization, and open circuit potential. The tests are compared with each other and with results from metallographic examinations. The structure was characterized by light and scanning microscopy. In addition, an analysis of the residual water was carried out using an ICP technique. The paper also includes a study of the various mechanisms that could affect the behavior of such coating types in a corrosive environment. Paper includes a German-language abstract.