No abstract

External method for the restoration of worn-out necks of large crankshafts by electroplating in flowing electrolyte with mechanical hardening at low temperatures (40...50 °C) is described. This method allows to prevent warpage of large crankshafts, to provide the required thickness (1.5...1.8 mm), the necessary microhardness (600...650 HV) and low roughness parameter (Ra = 1.25...2.5 μm). The use of iron chloride as electrolyte allows for quick pay-back at low material and energy costs.

The presented work reviews the research in the field of production of nanostructured composite materials based on copper, reinforced with carbon nanostructures. Particular attention is paid to the use of composites with high thermal conductivity as structural materials. The method of manufacturing a composite material based on copper is described in detail: modes of preliminary annealing, pre-pressing, hot isostatic pressing. The characteristics of the matrix and alloying components are given, and also preliminary treatment of copper powder and carbon nanotubes is described. Different mechanisms of component mixing are considered, the process of mechanical alloying in a planetary mill is described in detail, the results of measuring the thermal conductivity of samples are given. The mechanical characteristics of the samples are considered in detail: ultimate strength, yield strength, elongation. The degree of influence of surfactants on the uniformity of the distribution of alloying components and the mechanical properties of the composite material is determined.

No abstract