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This paper demonstrates the possibility of producing iron-or chromium-based nanophase hardfaced coatings by means of common arc welding methods (TIG, PTA). The appropriate composition of the alloys to be deposited allows to control the structural properties and thus also the coating properties of the weld metal. Specific variations of the alloying elements allow also the realisation of a nanostructured solidification of the carbides and borides with cooling rates that are common for arc surfacing processes. The hardfaced coatings, which had been thus produced, showed phase dimensions of approximately 100 -300 nm. Based on the results it is established that the influence of the surfacing parameters and of the coating thickness and thus the influence of the heat control on the nanostructuring process is, compared with the influence of the alloy composition, of secondary importance. The generation of nanoscale structures in hardfaced coatings allows the improvement of mechanical properties, wear resistance and corrosion resistance. Potential applications for these types of hardfaced coatings lie, in particular, in the field of cutting tools that are exposed to corrosion and wear.

Temperature-induced strain with, at the same time, reduced formability is, among other things, responsible for crack development in the range of high temperatures. For a more detailed examination of these so-called hot cracks, experimental measurements of the strain during the welding process have been carried out using neutron diffraction. The measurement of strain is important since it exerts decisive influence on the development of cracks.

During the last years, materials science has focused more and more on the development of nanomaterials. Reasons for that are the enormous advantages these materials can offer for various applications as their special structure yields the improvement of the material properties, such as hardness, strength and ductility. However, the production of especially “massive” nanomaterials is quite complex. The present study demonstrates the possibility of producing iron- or chromium-based nanophase hardfaced coatings with a thickness of several millimetres by means of common arc welding methods (TIG, PTA). An appropriate alloy composition allows to control the structural properties of the solidifying weld metal. Specific variations of the alloying elements enable the realisation of a nanostructured solidification of the carbides and/or borides with cooling rates that are common for arc surfacing processes. In the hardfaced coatings phase dimensions of approximately 100-300 nm were achieved. Based on the results it is established that the influence of the surfacing parameters and of the coating thickness and thus the influence of the heat control on the nanostructuring process is, compared with the influence of the alloy composition, of secondary importance. Several tests showed that the generation of nanoscale structures in the hardfaced coatings allows the improvement of mechanical properties, wear resistance and corrosion resistance. Potential applications for these types of hardfaced coatings lie, in particular, in the field of cutting tools that are exposed to corrosion and wear.

This paper demonstrates the possibility of producing iron or chromium-based nanophase hardfaced coatings by means of common arc welding methods (TIG, PTA). The appropriate composition of the alloys to be deposited allows to control the structural properties and thus also the coating properties of the weld metal. Specific variations of the alloying elements allow also the realisation of a nanostructured solidification of the carbides and borides with cooling rates that are common for arc surfacing processes. The hardfaced coatings, which had been thus produced, showed phase dimensions of approximately 100 -300 nm. Based on the results it is established that the influence of the surfacing parameters and of the coating thickness and thus the influence of the heat control on the nanostructuring process is, compared with the influence of the alloy composition, of secondary importance. The generation of nanoscale structures in hardfaced coatings allows the improvement of mechanical properties, wear resistance and corrosion resistance. Potential applications for these types of hardfaced coatings lie, in particular, in the field of cutting tools that are exposed to corrosion and wear.