Mechanisms Governing Surface Hardening of Porous Components During Plastic Deformation

In modern mechanical engineering and instrument-making industries, the range of applications of materials produced by powder metallurgy methods is expanding year by year. These materials are characterized by high material efficiency, the ability to manufacture components with complex geometries, a high degree of production process automation and overall economic feasibility. The effective use and long-term operation of products made from powder metallurgy materials in industry require thorough and systematic investigation of their technological, mechanical and tribotechnical properties. The scientific value of the article lies in the analysis of existing models that explain the behavior of porous materials produced by metallurgical sintering under conditions of surface plastic deformation and in overcoming their inherent limitations. For the first time, a new plasticity model is proposed that simultaneously accounts for changes in porosity and for the strengthening of the material matrix governing the plastic behavior of a porous body.The practical significance of the work lies in the development of several methods for surface hardening of sintered iron-based porous materials and in the selection of the most effective modes of plastic deformation based on the results of the conducted studies. New sintered materials synthesized from mixtures of iron and cast iron alloys are proposed, and techniques for surface strengthening through plastic deformation are developed.