Study of the effect of sharpness of cutting tools on the formation of defects in the surface finish in micro cutting titanium alloys

Abstract

The quality of machining of titanium alloys in the aviation and medical fields, characterized by the presence of micro vias, scales and surfacing on the treated surface, as well as the level of roughness is important in the manufacture of key parts. The quality parameters of the treated surface are influenced by many factors - cutting modes (cutting speed, depth and feed), cutting tool parameters (geometry of the cutting part, hardening coating, sharpness of the cutting wedge, etc.), technological equipment parameters (rigidity and accuracy), etc. The aim of the work was investigation of treated surface of titanium alloy VT1-00 when milling with small thicknesses of the shear layer, commensurate with the sharpness of the cutting wedge of the cutter. Method. The method of investigation of the treated surface during milling of titanium alloy on the micro level with the use of standard and high-quality carbide cutting tools is proposed. Results. Operating experience of the received carbide tool has shown that sharpness of a cutting wedge influences quality of the processed surface characterized by microwaves, scales and burrs, also by the roughness of the treated surface. On the basis of carried out researches it is established that for maintenance of conditions of normal cutting and chip formation it is necessary to provide sharpness of the cutting wedge characterized by the conditional entered radius of a blade rounding having values less than values of the sizes of grains of a processed material, that is re < 5 μm. Field of application. The obtained results of work allow to substantiate the recommendations on the required sharpness of carbide cutting tools used for milling of titanium alloys at the micro level. Conclusions. Experiments on the study of the process of cutting of titanium alloy VT1-00 at the micro level to determine the effect of cutting tool sharpness on the quality of the treated surface (microwaves, scales and burrs), allow to form recommendations on its initial state and determine performance.