Performance of flank face structured cutting tools in machining of AISI/SAE 4140 over a range of cutting speeds

It is well documented that surface structuring can improve the tribological performance of mechanical parts. For tooling, recent studies have focussed on structures applied to the rake face, the face in contact with the chip. This study investigates the impact of structures created on the flank face of the tool, which has not been widely explored. The flank face is an important area of focus because flank wear is a common end-of-life criterion for cutting tools. This article reports on the application of femto-second lasers to generate surface structures on the clearance face of the tool and their effect on tool-chip contact phenomenon and tool wear. A comparative study was conducted between machining with unstructured and structured cutting tools. Orthogonal cutting tests were performed over a range of cutting velocities, and flank wear, cutting power, compression ratio and tool-chip contact length were measured. The impact of a sticking and sliding contact was evaluated. Results showed a significant decrease in feed and cutting forces for a tool with flankfaced structures. The approach was a promising surface engineering innovation to improve the performance of cutting tools.