Problems related with abrasive wear of tangential-rotary picks during cutting process and its limitations, have been discussed in the present study. Essential for the parameters of cutting process geometrical, kinematic and material parameters of tangential-rotary picks and types of their wear, have been discussed. Testing procedure in aspect of the wear of tangential-rotary picks and their durability estimation, has been described. Manners of the abrasion of pick body and pick edge of the tangential-rotary picks, have been determined. Particular attention was paid to procedure of hard facing of the pick operational part and its influence onto mining process. Results of examination of tangential-rotary picks with hard facing layer on operational part near insert made of abrasion sintered carbide are also cited.Keywords: tangential-rotary picks, mechanical rock mining, abrasive wear, pad welding W artykule przedstawiono problemy związane z zużyciem ściernym noży styczno-obrotowych podczas procesu frezowania oraz sposoby jego ograniczenia. Omówiono istotne ze względu na proces skrawania parametry geometryczne, kinematyczne i materiałowe noży styczno-obrotowych oraz rodzaje ich zużycia. Przedstawiona została metoda prowadzenia badań noży w aspekcie szybkości ich zużycia oraz oceny ich trwałości. Przedstawiono sposoby zwiększania odporności na ścieranie korpusów jak i ostrzy noży styczno-obrotowych. Głównie skupiono się na metodzie związanej z napawaniem części roboczej noża oraz jej wpływem na proces urabiania. Przedstawione zostały również wyniki badań noży styczno-obrotowych z wykonaną na części roboczej napoiną w pobliżu wkładki z węglika spiekanego materiałem odpornym na ścieranie.Słowa kluczowe: noże styczno-obrotowe, mechaniczne urabianie skał, zużycie ścierne, napawanie

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The pearlite spheroidization in Fe-0.76%C high purity steel was investigated. The samples of a coarse pearlite microstructure were isothermal annealed at 700, 680, 660, 640 and 620°C for various times, up to 800 hours. For quantitative description of the spheroidization process stereological parameter, S V (ferrite/cementite interface surface density) was used. The activation energy 104.8±11.4 kJ/mol was found for the spheroidization process. This value shows good agreement with the activation energy for iron and carbon diffusion along a ferrite/cementite interface, so the coupled interface diffusion is the rule-controlling process.

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Results of beta forging of titanium alloy Ti-10V-2Fe-3Al and subsequent thermal treatment are presented, with analysis of the effect of the processing route on the final mechanical properties, correlated with microstructure of thermomechanically processed material. Investigation of response to high strain-rate hot-forging of microstructure and mechanical properties is focused on the effect of the strengthening mechanisms in the material after two common manners of deformation typical of that alloy. The effect of deformation conditions on final microstructure and mechanical properties was analyzed in three crucial stages of thermomechanical processing, e.i. after deformation, quenching and aging. In result, conclusions were formulated as for processing conditions promoting high strength and/or ductility.