The selective laser melting process is a growing technology for the manufacture of parts with very complex geometry. However, not all materials are suitable for this process, involving rapid localized melting and solidification. Tungsten has difficulties due to the high melting temperature. This study focuses on the possibility of processing a WC/Co/Cr composite powder using selective laser melting. Samples were fabricated and characterized in terms of density, defects, microstructure and hardness. Tests were conducted with hatch spacing of 120 μm and process speed of 40 mm/s. A constant laser power of 100 W and a powder layer thickness of 30 μm were used. A relative density of 97.53%, and therefore a low porosity, was obtained at an energy density of 12.5 J/mm2. Microscopic examination revealed the presence of small cracks and a very heterogeneous distribution of the grain size.

The main goals of the transport industry are lightweight and the increase in safety for passengers. Consequently, the choice of materials is very important. The materials adopted in recent years are lightweight alloys, such as aluminum and magnesium alloys, carbon fiber-reinforced polymers, and advanced highstrength steel (AHSS). In the automotive industry, five classes of AHSS are distinguished: dual-phase steel (DP), complex phase steel (CP), transformationinduced plasticity steel (TRIP), martensitic steel (MART), and press-hardened steel (PHS). [1,2] DP steels are ferritic-martensitic phase steels, which exhibit a strength between 450 and 1400 MPa depending on the amount of martensite. [3] Complex phase steels contain bainitic, martensitic, and ferritic phases and show higher formability than DP ones. [1] TRIP steels are characterized by a certain amount of retained austenite phase, which transforms into the martensite phase during the deformation. This effect helps the distribution of the strain and increases elongation, justifying the greater formability of TRIP steels compared to CP and DP steels. [1,4] Martensitic steels have high strength levels but show very low formability. Finally, the press-hardened steels are typically carbonmanganese-boron alloyed steels, [5] which are generally adopted in the press hardening (PH) process where the unformed blank is heated in a furnace up to the complete austenitization temperature, formed in the hot condition and finally quenched in the die. These steels are typically delivered in ferritic-pearlitic conditions and have, at the end of the PH process, almost doubled resistance levels due to the transformation into the martensitic phase due to the quenching phase. Among the PHS, the most common one is the 22MnB5; [5] however, other steel grades with higher carbon content are recently proposed to be used in the PH process. [6][7][8] PHS combined with the PH process allow to satisfy at the same time the requirements related to safety and those related to vehicle weight reduction, [9] therefore they are increasingly adopted in anti-intrusion applications of automotive structures (bumpers, doors, bodies-in-white).Current innovation trends are aimed at opportunities these AHSS offer in terms of tailored mechanical properties. [10][11][12][13][14] Currently, the stamped part designing with customized performances includes forming technologies that use tailor rolled blanks, tailor welded blanks, patchwork blanks, tailor tool tempering, tailor heating, and tailor cooling process. [15] A great deal of research has been carried out around the tool tempering approach in recent years. [12,13,16] With this approach, the tailored properties are achieved by exploiting different cooling conditions during the

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The capabilities of additive manufacturing (AM) techniques have been extensively examined in the literature. However, scientific gaps persist on the feasibility of realizing a coated component manufactured by using various materials processed by combining different AM processes. From this perspective, this study focuses on the manufacturing of a directed energy deposition (DED) coating by using 18Ni (300) maraging steel powder on AISI 316L components realized by laser-powder bed fusion (L-PBF), in order to assess the production of components with high geometrical complexity combined with high mechanical surface properties in selected areas. The quality of the manufactured coatings was assessed in-process through the implementation of an optical monitoring system and real-time image processing. In addition, an in-depth metallurgical analysis (microstructural and chemical) of the interface between the DED coating and the L-PBF component was carried out. Finally, hardness tests were performed on both the as-deposited and heat-treated coatings to confirm the high mechanical performance of the final component surface. The results revealed the potential of producing cost-effective and geometrically complex parts, such as molds or tools with internal cooling channels, that implement mechanically high-performance surfaces.

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