Surface roughness after turning the austenitic 08X18H10 steel alloyed with copper and manganese depending on structure and properties formed by the intensive plastic deformation

Various industries are widely using the austenitic stainless steels, and these steels possess the potential to improve their mechanical properties through alloying and deformation machining. However, such material improvement could also affect the quality of its machine cutting. The paper studies the influence of intensive plastic deformation on structure and properties of the 08X18H10 steel alloyed with copper and manganese, as well as on the quality of its machining in turning under different structural states. It was established that the use of multilateral forging led to formation of a heavily deformed subgrain structure with the high dislocation density in the steel under study, and subsequent rolling caused additional formation of the differently oriented deformation microtwins and packs of nanotwins. These structural alterations contributed to increasing the strength and micro-hardness of the material. Analysis of the machine turned surface relief of the samples showed that using the intensive plastic deformation made it possible to significantly reduce the Ra and Rz roughness parameters compared to those samples not subjected to intensive plastic deformation. It was found that an increase in feed led to the growing micro-hardness of the material thin near-surface layer and to its smoother alteration in depth from the machined surface.

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