Effect of direct laser re-melting processing parameters and scanning strategies on the densification of tool steels

The effect of processing parameters and scanning strategies on the processing of H13 tool steel by direct laser re-melting (DLRM) has been investigated. The density of samples produced was significantly increased by the use of a modified knit-scan strategy. The effects of line spacing and scan speed were also studied, with optimum values of 0.10 mm and 100-150 mm/s, respectively, being established. Even with the optimum conditions, the maximum density achieved with H13 tool steel was about ρ = 6.47 g/cm3 (about 84% of its theoretical value), significantly lower than that which has been obtained with 316L stainless steels.