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Electron beam additive manufacturing (EBAM) offers a high degree of control over highly complex structures. An EBAM alloy in development by the company VBN Components, specialising in wear-resistant AM steel, has been found to develop microcracks which has been partially characterised in this paper.

EDS analysis of microcracks in the bulk of the alloy samples has indicated that two carbides congregate in and around the cracks. Thermodynamic simulation of the system in the software Thermo-Calc indicated that the carbides are likely to be MC with V and M6C with Fe, Mo, and W. EBSD analysis was performed, but only a small amount of data was achieved due to difficulties with the sample preparation. From the small amount of data it was still observed that there might be a relation between cracking and large misorientation angles between grains, this however needs more research. Since sufficient sample preparation for EBSD analysis finally was achieved, it is strongly suggested that more samples are prepared according to guidelines presented in this work, so that the correlation between cracking and misorientation angle can be further investigated. Hardness measurements through nanoindentation around cracks proved inconclusive in determining statistically significant differences to hardness in crack-free areas. The overall result of the characterisation indicates both grain orientation and precipitated carbides to be linked with microcracks in the alloy; which should be studied further.