Study of physical and mechanical properties of samples obtained by SLM technology. Part 1. Strength limit

Additive technologies are currently being actively implemented at the enterprises of the shipbuilding industry. After the successful testing of fused deposition modeling (FDM), stereolithography (SLA) and multi jet modeling (MJM) technologies in terms of prototyping and production of polymer products, the general vector of development seeks to master the technologies of metal printing of blanks and finished parts. Work in this direction is being carried out at a number of enterprises and the most popular technologies in this aspect are selective laser melting (SLM), wire arc additive manufacturing (WAAM) and high-speed direct laser deposition (HSDLD). At the moment, the interest of a number of shipbuilding companies is the possibility of producing blanks for parts according to castings drawings using the SLM technology. However, it should be noted that in the literature there are conflicting data on the properties of the samples obtained, in particular, regarding the presence of anisotropy of strength characteristics and the compliance of geometric deviations with existing standards. It is interesting in this regard to manufacture products of complex geometry from stainless steels, which can be used in the manufacture of levers, forks, housings of special equipment, as well as supercavitating screws and elements of hydrofoil consoles for small vessels. This paper describes the physicomechanical characteristics and geometric deviations of samples obtained by the SLM technology on a Laser Cusing M2 setup made of 316L stainless steel. Specific ideas are given about the anisotropy of strength properties and the compliance of the geometry of the samples with the requirements for the manufactured products. The presented materials can serve as a starting point for carrying out strength calculations of products, taking into account some specifics of additive technologies and, in particular, the SLM process.

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