Fully dense components built using selective laser melting exhibit mechanical properties equivalent or even better than those of parts produced by conventional manufacturing  . But building components using SLM sometimes requires external support structures. These support structures are necessary for a few reasons: they strengthen and fix the part to the building platform, they conduct excess heat away and they prevent warping or complete build failure.
They make non negligible impacts on production yields and costs. These additional structures increase build time, build costs as well as post-processing time and complexity.
In order to derive the build optimal orientation susceptible to minimise (eliminate?) the quantity of supports, it is necessary to analyse the component’s geometry and its limitations.
Sources of manufacturing defects and build failure 
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Laser Direct Deposition