Influence of the cutting edge on the surface integrity in BTA deep hole drilling - part 1: Design of experiments, roughness and forces

Abstract

The BTA deep hole drilling process is used to machine deep bores with a large diameter. The cutting process, consisting of the material removal by cutting edge and the surface burnishing by the guidepads influence the surface of the bore. To separate the impact of the cutting edge from that of the guidepads on the surface of the bore and the subsurface zone an experimental model setup in analogy to the BTA process was developed. This paper covers the differences to the conventional BTA deep hole drilling, the experimental boundary conditions and the measurement of the surface roughness. The results are compared to previous analysis of the surface integrity of BTA deep hole drilled specimens. Furthermore, conclusions about the process forces are drawn from the documented loads occurring for the machine axes. In part 2 of this study, the surface integrity of the specimens is further analyzed using destructive and non-destructive methods.