Introduction: In modern vehicles, new enhancements are being sought for engine components, break discs, and valves, using light-weight materials which are applicable not only in conventional cars but also in electric vehicles. The utilization of novel additive manufacturing aims to reduce energy loss and mechanical stress, improving component longevity at a lower cost.
Method: Theeffective hardfacing of silicon carbide (SiC) over stainless steel was achieved using a Rofin Sinar Nd:YAG 2 kW robotized laser system with powder feedstock. Different Metal Matrix Composites (MMCs) were manufactured using Laser Directed Energy Deposition (DED-LB), making it possible to additively manufacture near-net-shaped parts while having the freedom to obtain variable geometries for the surface layout. Samples were prepared from teh following flat products of EN 10088: X2CrTi12(1.4512, AISI 409), Х15CrNi25-20 (1.4840, AISI 310), X5CrNi18-10 (1.4301, AISI 304), and X1CrNiMoCuN20-18-7 (1.4547, UNS: S31254). The reinforcement comprised a fine carbide powder of SiC, and the MMCs were produced after the solidification of the molten mixture. The study included an assessment of the interface zones and measurement of their microhardness, as well as microstructural analysis with visual defect evaluation focusеd on porosity and microcracking detection.
Results: In order to increase durability and heat and wear resistance, advanced MMC sample components for various vehicles applications were explored. In one layer with a thickness of 1.5 mm, composed of X1NiCrMoCuN20-18-7 and SiC, the hardness characteristic was observed to be about 25 MPA higher than that experimentally obtained for the base material. For the same MMC, the carbide–metal interface zoneswere investigated.No cracks were observed, and it displayed a porosity of ≈ 1.57 %. DED-LB MMC possess excellent thermal stability and resistance to abrasion.
Conclusion: Laser application allows various geometric applications on the surfaces of car parts. The appropriate selection of component phases can enable thedesign of parts with specific functionality, where the interaction between the microstructure and properties is complex.
Funding: The author acknowledges support from project BG16RFPR002-1.014-0005.
