Microstructure and Mechanical Characterisation of SLM Processed Haynes® 230®

Selective Laser Melting (SLM) enables the production of complex near-net-shaped parts especially out of difficult to machine Nickel based alloys like Haynes® 230®. However, exact knowledge of the SLM processing windows and the corresponding mechanical properties is essential for a target-oriented part design as well as post process planning. Especially the high cooling rate of the small weld pool characterizes the SLM process and is known to cause material microstructures different to standard wrought or cast material. Samples are built with different heat input levels and are analysed for their density, pore- and crack sizes. Optical and scanning electron microscope (SEM) and electron backscatter diffraction (EBSD) are used to characterize the material microstructure. Static tensile test samples were built in either 0° or 90° orientation for the evaluation of mechanical properties at room temperature and anisotropy as well as the influence of the different heat input levels are assessed. It is shown that the alloy itself is well suited for the SLM process allowing the consolidation of nearly defect free material with improved mechanical properties with regards of yield and ultimate tensile strength compared to cast as well as wrought material.Mechanical Engineerin