Verification of mechanical properties and surface topography of PH1 stainless steel samples obtained by selective laser melting

Abstract

Nowadays, additive technologies are used to create physical models, prototypes, samples, tooling, and the production of plastic, metal, ceramic, glass, composite components, and components made of biomaterials. The greatest technological interest is the production of final parts from metal alloys. This paper presents the results of studies of the topography of differently oriented surfaces of PH1 stainless steel samples made using the method of selective laser melting. The surfaces were studied in the plane of construction, perpendicular to the platform, at angles of 45o and 135o. For each surface under consideration, the roughnesses Ra, Rz were determined and a profile was constructed. The findings showed high stability of the topography of the surface layer of the grown material. To confirm the quality of the obtained samples, they were synthesised and tensile tests were carried out. The established characteristics of the elastic modulus, the tensile strength and the corresponding deformations are consistent with the previously determined properties of samples grown using selective laser melting technology and datasheet specifications. According to the results of mechanical tests, the microstructure of the fracture surfaces of the samples was investigated. It is established that the destruction of samples under tension occurs by a viscous mechanism with the implementation of a combination of shear and pit-porous types of destruction. The study of the topography of differently oriented surfaces is carried out – in the plane of construction, perpendicular to it and at angles to the platform 45 and 135o. It is shown that the best surface quality corresponds to two planes – parallel and perpendicular to the plane of the construction platform. The average values of their roughness were Ra ~ 0.6 µm and Rz ~ 4 µm. The quality of the surfaces located at an angle is significantly inferior to the first two. A change in the surface quality depending on the angle of inclination was also observed.