The microstructure evolution, mechanical properties, and tribological properties of deposited metal Fe-C-Cr-Ti-B alloy by self-shielded flux-cored wire electrode (FCAW-S) with the introduction of exothermic addition and without it are investigated. Experimental studies showed that the introduction of CuO -Al exothermic addition in the composition of the wire core filler reduced the grain size of the deposited metal. Furthermore, X-ray diffraction analyses show that the boride layer contained FeB, Fe2B, and Ti(C, N) phases. Depth-sensing indentation was used to determine hard phase properties (hardness, Young's modulus and plasticity coefficient). It was shown that introduction of CuO -Al exothermic addition in the core filer increased the mechanical properties of deposited metal. The latter can be explained by the grain size decrease, as well as a change in the phase composition of the deposited metal due to additional copper alloying. This transformation is accompanied by an increase in hardness and in the Young's modulus. Tribological tests showed the effectiveness of introduction of the exothermic addition CuO -Al into the filler core for increasing the wear resistance under conditions of 3-body abrasive particle wear.

In this research, the corrosion behaviour of the Fe-C-Cr-B-Ti alloying system deposited alloys applied by flux-cored arc welding are studied. Samples of deposited alloy with a high content of chromium (13% by weight of Cr) received

No abstract

No abstract

The tribological properties of complex polymeric materials, which include epoxy and polyester resins, two hardeners and two microdispersed fillers: mica-muscovite, copper (II) oxide, were investigated in the work. The results of the testing of specimens at dry friction and in the lubricant were analyzed. It is proved, that the antifriction properties of the composite depend on its composition, formation technology and testing conditions. It has been experimentally determined, that the material which was tested in the lubricating environment -I m = 0.25-0.30 mg/km, f = 0.03-0.04, differs with the improved indexes of wear rate and friction coefficient. As a result of the analysis of investigated microsurfaces studied by optical and electron microscopy, the phase heterogeneity of the composite material system was identified. It contributes to the reduction of the running-in distance of the specimen, and indicates the uniform distribution of the filler particles on the surface, has been found. The elemental composition of the compound was determined, which indicates the direct involvement of fillers in the process of friction. A change in the ratio of atoms on the specimen surface before and after the test was found. The results of the study of the surface in the phase contrast mode correlate with the results of the data obtained by electron microscopy.