The present study is devoted to the surface processing technology of 3Х2В8Ф hot-work tool steel and the effect on its operational properties. The surface processing included thermal-chemical treatment (TCT) and surface finishing. Boroaluminizing (joint diffusion with boron and aluminum) was chosen as a TCT method. Steel samples were covered by a treatment paste, containing boron carbide, aluminum and sodium fluoride powders. The exposure time was 2 hours and the treatment temperature-950°C and 1050°C. The surface finishing was carried out by an elbor grinding tool to coordinate grinding on a vertical milling machine. The diffusion layers with a composite structure were formed on top of the steel as a result of TCT at 1050°C. Processing at 950°C resulted in a diffusion layer formation with layered structure. The surface roughness after boroaluminizing have increased from initial Ra 1.5 μm to Ra 4 μm after 950°C TCT and to Ra 7.7 μm after 1050°C TCT. The roughness increase was due to surface reactions with air components, such as oxygen and nitrogen, as well as their penetration to the upper zones. Applying surface finishing as a final mechanical operation (FMO) resulted in roughness reduction from the above mentioned values to Ra 0.09 μm to Ra 0.43 μm, respectively. In addition, the upper redundant zone of the layer was removed with no damage done to the inner zones by means of FMO. The provided surface quality ensures sufficient operational properties of the machine parts and details made of this particular steel.

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The influence of the technological parameters of hot sheet stamping on the shaping of parts made of titanium alloy - forgings for helicopter screw linings is investigated. It is shown that the most suitable method for the manufacture of such parts is hot stamping with preheating. At the same time, the main technological requirement is the uniformity of heating, the need to exclude the movement of heated workpieces, as well as negative transformations in the material at micro and macro levels.

Methods of mathematical modeling, basic technologies and methods of modeling in various design systems of the stamping process are considered. The canonical equations of temperature stresses are obtained, which make it possible to obtain a picture of the temperature distribution over the workpiece area during heating. A mathematical model has been developed for a thin metal strip during heating; thermal stresses arising in it due to uneven heating have been described. Numerical modeling has been carried out on the basisof field data, which will allow verification of the automated environment for the selection of functional and design schemes and the calculation of the parameters of heating devices in hot volumetric stamping of workpieces in terms of speed, energy efficiency, heating quality: accuracy of achieving specified temperatures and maximum heating uniformity. By areas, ease of use and readjustment, resource, reliability and maintainability. The proposed system will include the following CAD elements: databases and rules for operating with them, calculation modules, modules for selecting and matching options.

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