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The roughness of a milled surface is investigated for AISI 321 austenitic stainless steel with different structure and mechanical properties. The grain size is modified by familiar methods of intense plastic deformation: ABC pressing and rolling. For milling, stainless-steel plates of different thickness are prepared. Cylindrical hard-alloy mills are employed. Analysis of the microgeometry of the machined surface indicates that change in structure and mechanical properties by intense plastic deformation decreases the height parameters Sa and Sz of the roughness by factors of 1.8–6.7.

On account of their improved physicomechanical characteristics, materials with ultrafine-grain and nanocrystalline structure are of great interest in manufacturing and elsewhere. There has been considerable research on methods of producing such materials. The techniques most commonly used to produce three-dimensional ultrafine-grain materials are equal-channel angular pressing; cumulative rolling; intense rolling; and friction with mixing. However, little information is available regarding the influence of the shaping conditions on the structure and properties of three-dimensional ultrafine-grain materials. Accordingly, there is a pressing need to find effective structuring and shaping methods for the manufacture of parts from ultrafine-grain materials with enhanced performance. Analysis of structuring and shaping methods indicates that the production of high-quality parts from three-dimensional ultrafine-grain and nanocrystalline materials calls for the development of processes, equipment, and tools such that the physicomechanical characteristics and structure of the materials formed by intense plastic deformation are retained.

The influence of cutting (milling) on the surface roughness and undulation of AMg2 aluminum alloy with regular and ultrafine grain structure is considered. In the machining of materials with ultrafine grain structure, the surface quality is better than for materials with regular grain structure.

Turning by tools that are characterized by a linear or curved cutting blade but have no cutting tip is studied experimentally. The influence of the depth and cutting speed, the supply, and the cutter inclination on the components P z and P y of the cutting force is investigated in inverse and direct cutting.