VDM Alloy 780 is a novel nickel-based superalloy using γ’-precipitation hardening thus enabling application temperatures of up to 750°C. However, when using Laser Metal Deposition (LMD) as manufacturing process, the resulting parts show anisotropic mechanical properties and directional grain growth in build-up direction. These effects as well as the grain coarsening caused by low cooling rates lead to reduced mechanical properties compared to wrought material. In order to achieve comparable mechanical properties, LMD-manufactured components must be subjected to post-heat treatments.


In this work, the influence of post-heat treatments on the mechanical properties and microstructure of powder-based LMD VDM Alloy 780 components, consisting of solution annealing and double aging is investigated. In addition, different HIP cycles are applied to determine the influence on the porosity and the mechanical properties.


The samples are examined metallographically using optical microscopy and scanning electron microscopy. The grain orientation along the microstructure is determined by electron backscatter diffraction analysis of the heat treatment stages. To evaluate the mechanical properties, tensile tests in perpendicular and parallel directions as well as macro hardness measurements are carried out.


The results show that the ultimate tensile strength and the macro hardness were increased by post-heat treatments. The porosity in the component can be reduced by the HIP process, thus improving the mechanical properties further.