ON THE IMPACT TOUGHNESS OF HEAT-TREATED AISI 430 STAINLESS STEEL FABRICATED BY LASER-POWDER BED FUSION

In recent years, additive manufacturing techniques have attracted increasing interest in both academia and industry due to the great advantages of fabricating near net shape components with full design freedom, reduced lead time and limited waste materials. In the present study, AISI 430 stainless steel powders were used to fabricate via the laser-powder bed fusion (L-PBF) process fully dense parallelepiped samples in vertical and horizontal directions according to the building platform. According to the literature, after the printing production, two different post-fabrication heat treatments (PFHTs) were performed to increase the toughness of the specimens. Impact V-notch subsize impact Charpy tests and microstructural analysis through optical and scanning electron microscopy were carried out to correlate the impact strength results with both building directions and the peculiar microstructures generated by the two PHFT routes. Based on the results, the two PFHTs exert a positive effect on the impact strength of the AISI 430 stainless steel fabricated by L-PBF.