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Wear during dry sliding friction depends on the features of deformation accumulation. The regularities of this process are traced on polycrystalline Hadfield steel with structure certified by Electron Backscatter Diffraction (EBSD). The root mean square values of the vibration acceleration and the friction coefficient change a little during friction. The grain deformation and the volume of the material involved in deformation are increased by friction. The area with deformed grains increases during the first three test cycles. The deformation propagation from the friction surface is slower than in single crystals. The activity of grain deformation is determined by a high value of the Schmid factor for the normal load and the friction force. The values of the shear trace parameters of grains are similar to those of the single crystals. The grain orientation difference and the hardening effect of grain boundaries delay the deformation accumulation and destruction, increasing the wear resistance of the polycrystalline steel compared to the single crystals. [ABSTRACT FROM AUTHOR]

A procedure for the synthesis of a CdSiP2 compound from the initial elementary components in a gradient thermal field has been developed. The phase and chemical composition of the synthesized and recrystallized material is confirmed by the data of X-ray diffraction analysis and scanning electron microscopy with an energy-dispersive system. The polycrystalline material obtained by the developed method will be used to grow bulk nonlinear optical CdSiP2 crystals. [ABSTRACT FROM AUTHOR]

The paper deals with the dislocation substructure of polycrystalline FCC alloys modified by plastic deformation at a distance from the area of the specimen fracture. Observations are performed using the transmission electron microscopy. Cu-Al alloys with grain size ranging from 10 to 240 μm are studied in this paper. The parameters of the dislocation substructure are measured and their variation is determined by the increasing distance from the fracture area. It is shown how the grain size influences these processes. The different dislocation substructures which determine the specimen fracture at a mesocscale level are found herein. [ABSTRACT FROM AUTHOR]

The results obtained from an experimental study on the structure of deformed polycrystalline materials of the meso- and microscale grain size, using transmission electron microscopy, are presented. The slip line pattern, accumulation of the scalar dislocation density and dislocation density components, lattice curvature-torsion, and internal stresses are investigated. The difference between the characteristics of the defect polycrystalline structure at the micro- and mesoscale levels is established. [ABSTRACT FROM AUTHOR]

The evolution of dislocation substructures formed in polycrystalline Cu−Al and Cu−Mn alloys undergoing large plastic deformations is studied, using transmission electron microscopy. Microband and fragmented substructures are examined. The Al and Mn alloying element concentrations for which the substructures are formed have been found. The mechanisms involved in the formation of the substructures during the substructural evolution in the alloys subjected to deformation have been revealed. Parameters describing the substructures under study have been measured. The dependence of the parameters on the flow stress has been established. [ABSTRACT FROM AUTHOR]