Technological machinability of materials in processes of abrasive machining. Part 1. Concept and formal description

There is no definition of the term “machinability” in regulatory documentation, leading to huge quantity of its different articulations and evaluation criteria, often opposite to each other. In most cases, machinability is understood as material's possibility (characteristics) to undergo machining. But each cutting process is aimed not only on removing metal, but on removing set allowance, assuring process quality requirements, machining accuracy, etc., which fulfilling is directly linked with material machinability degree. Therefore, different researchers have added the machinability definition by its determining criteria, for example, machinability per surface roughness, machinability per tools durability, etc. This situation leads to even larger conceptual uncertainty. Taking into account constant growth of requirements to surface layer quality, machining accuracy, etc. in modern mechanic engineering, present meaning of the machinability term does not reflect physics of the described process. It is necessary to understand the machinability not only as the martial feature under certain process limitations, but also as a complex technological factor. Based on analysis and summarizing technological requirements to goods after abrasive machining, article suggests scheme of forming machinability feature as material resistance to destructing, limited by complex of technological limitations. This allows forming technological machinability term meaning, taking into account not only material resistance to cutting, but also assuring all technological limitations and requirements to processed detail surface. Complex of technological limitations and control parameters was formed in order to implement the materials technological machinability concept. Formalization of this complex allowed working out technological machinability term mathematical description, allowing structurally including and usage of all present theoretical and experimental results in the field of abrasive machining.