Industries that rely on additive manufacturing of metallic parts, especially biomedical companies, require material science-based knowledge of how process parameters and methods affect the properties ...of manufactured elements, but such phenomena are incompletely understood. In this study, we investigated the influence of selective laser melting (SLM) process parameters and additional heat treatment on mechanical properties. The research included structural analysis of residual stress, microstructure, and scleronomic hardness in low-depth measurements. Tensile tests with specimen deformation analysis using digital image correlation (DIC) were performed as well. Experiment results showed it was possible to observe the porosity growth mechanism and its influence on the material strength. Specimens manufactured with 20% lower energy density had almost half the elongation, which was directly connected with the porosity growth during energy density reduction. Hot isostatic pressing (HIP) treatment allowed for a significant reduction of porosity and helped achieve properties similar to specimens manufactured using different levels of energy density.
The purpose of this paper is to study the tribiological behavior of (steel/porous iron), (steel/steel) and (steel/bronze) tribopair with micellar copper oxide, hexagonal boron nitride (h-BN), Lithium ...grease Liten LT43 and base oil, transformer mineral oil, and mineral oil SN650 as lubricants. The results are discussed in the form of performance such as wear surface, friction coefficient, weld point, limiting load wear and load-carrying capacity. It is found that (steel/bronze) friction pair contacts develop into a (copper/copper) contact along the sliding time. Worn surfaces were examined using XPS to determine the friction mechanism. The lower friction by additives is based on the formation of metallic copper tribofilm, and lamellar h-BN lubrication mechanism is discussed.
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