Iron based materials are classified as being more health and environmentally friendly as well as cost-effective (material and machining costs) compared to typical materials used for wear protection applications (e.g. cermets). The advantage which is seen in using very fine powders (< 15 μm), is their potential to spray relatively thin, dense near-net-shape coatings with comparable smooth surfaces. This can lead to lower coating as well as machining costs. In this work fine Fe-based powders (-15+5 μm) have been used in order to produce wear resistant coatings for applications in the printing industry by means of air plasma spraying (APS). With regard to oxidation problems of such fine Fe-based materials a shroud for the air plasma spraying system has been developed and deployed. The resulting coatings have been analysed with respect to the microstructure, micro hardness, chemical and phase composition as well as surface roughness (as-sprayed). The economical aspects have also been considered.

The objective of this work is the development and application of Fe-based wear- and corrosion-resistant coatings with uniform density and even coating surfaces. The coatings obtained were analyzed with respect to microstructure, hardness, and surface roughness.

Hypoeutectic AlSi engine blocks of modern passenger cars are generally equipped with cast iron liners in order to provide cylinder running surfaces that meet the tribological requirements. A very promising alternative to the use of cylinder liners lies within the application of thermally sprayed coatings onto the walls of cylinder bores as friction partners for the piston rings. This work describes the development of a novel iron based wire feedstock as well as its application by the Plasma Transferred Wire Arc internal diameter coating system. The material developed within the frame of this work leads to partially amorphous coatings with embedded nanoscale precipitations if processed by thermal spraying. The coatings were applied onto the inner diameters of test liners made of Aluminium EN AW 6060 and onto cylinder bore walls of in-line 4 cylinder engines. All substrates were mechanically roughened in order to obtain high bond strengths of the sprayed coatings. The coatings microstructure was analysed by light optical microscopy, hardness measuring by transmission electron microscopy. Furthermore the oil storage capacities of the honed surfaces were determined.

Crank cases of modern car-engines are made in general of light metal alloys, mostly aluminium alloys. Due to the low hardness of these materials, the use of cylinder liners, in general made of grey cast iron is required. The use of cylinder liners also leads to several disadvantages, such as the increase of the engines weight. The aim of this work in the long term is to replace these cylinder liners with a thermally sprayed nano-structured composite coating, characterised by high hardness. Therefore in this study a coating process employing a plasma transferred wire arc unit and a cored wire are used.