International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

A methodology has been developed for obtaining of porous castings from Al and aluminum A356 alloy. The methodology includes introduction of Ca into the melt for viscosity increasing and homogenization by mechanical stirring. This is followed by addition of TiH2, homogenization, subsequent formation of the porous structure and crystallization. Tests were carried out on specimens of the castings involving abrasive wearing under dry friction conditions on a surface with hard-attached abrasive particles.

An analysis of the prospects for the development of FDM printing technology has been carried out. The paper studies the possibility of obtaining polymer products based on polyamide 6 and its compositions by layer-by-layer deposition. Tests of the strength indicators of the printed experimental products were carried out. The mechanism of the influence of the composition and modes of formation of printed products on their strength characteristics is proposed. The influence of the composition of the composite polymer material based on PA6 on the quality of printing products has been studied. Methods for controlling the shrinkage parameters of products obtained by
layer-by-layer deposition are proposed. The obtained results of the study can be used in the development of composites for the production of polymer filament to ensure the process of FDM printing of polymer products, including for the needs of mechanical engineering.

The object of research – the natural glycoalkaloid solanine as a possible inhibitor of acid corrosion of steel St3. Modern data on the structure and physico-chemical properties of solanine, such as amphiphilicity, surface activity, basicity, characteristic of modern organic corrosion inhibitors, are presented. The basic concepts are defined: basic nitrogen, solanine amphiphilicity, mass and volume corrosion indicators, corrosion inhibitor, degree of protection, corrosion inhibition coefficient. The literature data on the corrosive activity of lactic acid (MC) are presented and characterized.

Four types of aluminium alloys (two casting and two plastically deformable) were used in the present study. A special press mould for compacting the aluminium alloy chips and subsequent extrusion of the resulting compacts was designed and manufactured. The compressive strength of the obtained samples was investigated, in relation to their chemical composition and technological parameters during their fabrication. The results of the research are presented in tabular and graphic form. It was established that compacted samples from AW-6082, AC-48000 and AW-2024 alloy possess high compression strength (in the range of 766 – 866 MPa) under compression loading at 60% deformation. It seems that the extrusion process improves compression properties of AW-2024 and AC-48000 alloy but has negative effect on AW-6082 and AC-42000.

Technological first-order phase transition is obtain base process of material science by numerical experiments at use of finite elements method (FEM). The history of movement and the geometry of the front in the first-order phase transition are investigated. A free first-order phase transition was investigated to estimate the local place of the liquid residue. Mathematical model is Stefan-Schwartz task in 3D case. The corresponding temperature fields of a free and technological first-order phase transition are presented. Engineering information is local phase transition conditions is shown of macro-level with the local transition time and volume at the front is assumed.