Direct laser remelting of iron with addition of boron

Abstract

Previous work has shown that increasing the carbon content of steel powders has a deleterious effect on their direct laser remelting (DLRM) processability. Therefore, other interstitial alloying elements have been investigated to identify if they produce similar effects. This paper reports on the processing of iron powders with small additions of boron by DLRM. It was found that the addition of boron, in the form of iron boride, increased the width of the scanned tracks for a given set of laser parameters and reduced the tendency for the tracks to spheroidise. Boron addition did not have a deleterious effect on processability and to some extent increased component density for a given set of conditions. Other steel samples were processed that contained small additions of iron boride and titanium powder. The inclusion of titanium improved the bonding of the sample to the substrate and reduced the extreme hardness of the material. However, it also significantly reduced the processability of the material.