Performance Evaluation of Tools Made of Super Hard Material CBN during the Renovation of Components of Harvester Machinery

An investigation was conducted to examine the influence of hard alloy turning tools and BN-based super hard materials on the performance characteristics during the finish turning of components with the deposition of Surfacing wire (Sw)- 40Cr8Si2 (HRC 50-58). Upon deposition, the surface undergoes a significant increase in hardness, resulting in a hard-faced item with a rough, uneven, and undulating surface. Consequently, a machining process is employed to provide a smooth finish and ensure the desired dimensions are maintained. The variables in question are as follows: transverse chip shrinkage ξ, frictional coefficient during modeling μ, vertical component of cutting force Pz (in Newtons), cutting temperature θ°С, machined area F (in square meters), cutting-tool life before reaching a specified blunting criterion Т (in minutes), maximum cutting length at the optimal wear of cutters L = T-V (in kilometers), and the relative flank wear of cutters at their specified resistance. The symbol “hoз” represents the ratio of hз to L, where hз is measured in micrometers (µm), and L is measured in kilometers (km). It is used to describe the roughness of a machined surface. The performance characteristics of turning cutters in this investigation were measured in terms of Ra (µm). The techniques of experimental optimization of surface roughness that have a significant influence on resurfaced hard turning are also investigated.