Platov South Russian State Polytechnic University (Novocherkassk, Russia):

S. N. Sergeenko, Cand. Eng., Associate prof., dept. “Technology of machine-building technolgical equipment”, e-mail: sergeenko@gmail.com

The laws governing the compaction of Fe – FeMn – C mixtures treated in a planetary mill and the consolidation of 110G13 powder steel with activated sintering have been established. With an increase in the compaction pressure, a continuous increase in the relative density of the molding is observed for the studied interval of variation in the duration of mechanical activation (0–2.01 h). The transition from mixing technology to the mechanical activation of the 110G13 powder steel mixture increases the minimum defect-free compaction pressure. The increase in the duration of mechanical activation leads to the decrease in relative density of the molding for all investigated values of compaction pressure. The parameters of the compaction equation for mechanically activated charges of 110G13 powder steel have been determined. At the initial stage of mechanical activation, a decrease in the maximum pressure is observed, ensuring the compaction of a non-porous material and the increase in the share of plastically deformed volume. A modified compaction equation was proposed, which takes into account the duration of mechanical activation. The extreme dependence of the influence of the duration of the charge mechanical activation on the relative density of 110G13 sintered powder steel was established. To assess the activated consolidation, the volume  strain of the sintered material was calculated. The Spline 3D model of theeffect of mechanical activation and compaction pressure on the volumetric deformation of pores during the consolidation process was constructed. The relationship between the density of sintered 110G13 steel and the volumetric deformation of the pores was revealed. The optimal time of mechanical activation (1.05 h) ensures the maximum degree of material consolidation. The transition from mixing technology to mechanoactivation leads to change in the consolidation pattern of the 110G13 powder steel from softening to quasi-isotropic compaction.

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