In situ fabrication of aluminide coatings and rapid prototyping by laser cladding

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The intermetallic compound ruthenium aluminide (B2-RuAl) possesses a unique combination of properties. It is reported to have high ductility at room temperature, good oxidation and corrosion resistance as well as high thermal stability. The industrial application of RuAl is hindered by problems which arise during processing with conventional methods.It had therefore been the aim of the initial DFG-proposal to evaluate the possibility of laser cladding RuAl . Crack-free Coatings and three-dimensional structures have successfully been produced using elemental powder blends in the context of the first project. Furthermore, their phase compositions have been revealed in detail.It is the first aim of the follow-up project to optimise the manufacturing process for the coatings and structures in a way that they can be more easily transferred to industrial applications. Therefore, the powder mixtures shall be mechanically alloyed before the process. Laser cladding with mechanically alloyed powder has the potential to combine the advantages of the use of elemental powder mixtures and pre-alloyed powder. Since the iterative procedure during process optimisation as well as the used characterisation methods have shown to be very successful during the first project, they should be kept during the follow-up project.Secondly, the friction properties and wear resistance of the coatings under dry conditions should be evaluated and compared to technically relevant materials since these properties are crucial criteria for the applicability of the aluminide coatings and since they have not been tested for RuAl, yet.