THE CHOICE OF CUTTING TOOLS AND FORECASTING ITS PERSISTENCE IN THE MACHINE PROCESSING OF PERMALLOY 50N

Abstract

Soft magnetic materials are widely used in modern technologies, processing of which is difficult and requires further research. Analysis of the literature revealed that the factories in the finishing operations are rarely used parts of the subtle turning of permalloy alloys, as a more efficient process, replacing the grinding. The correct choice of tool marks, primarily related to its effect on performance and quality characteristics of these alloys. To the qualitative characteristics of permalloy 50N primarily include the microhardness of the surface layer, the degree of work hardening, surface roughness and magnetic properties. This task is greatly complicated by a large number of tool materials - high-speed steels, hard alloys, tungsten carbides, mineral ceramics, superhard materials. Studied the effect of tool material brand on the magnetic properties of permalloy 50H at the thin turning on the representatives of different tool material groups "P", "M" and "K" on the international system JSO. The tool materials diagram ranged by size drop of the permalloy 50H magnetic properties was constructed. The best alloy instrument brand is determined - tungsten carbide KNT16, which provides the minimum fall value of the maximum magnetic permeability permalloy 50H. Stability dependence, which allows to predict tool stability for a given cutting conditions while limiting it to a critical wear limit in the processing, was submitted. The sharp drop in the magnetic properties of permalloy 50H while processing by the wolfram containing tools is explained into the neutron scattering experiments, in which the introduction of wolfram atoms in a nickel matrix causes a decrease of the atomic momentum in the large volume of the metal matrix around the impurity atoms, since the lattice parameter of wolfram is twice bigger than the lattice parameter of nickel.