Study increase the mechanical characteristics of tool materials by cryogenic treatment

Vladimir Puchkin,Olga Sumskaja,Ilya Turkin,Larisa Salanti,Vladimir Kornienko,A Lukyanov,E.H Abderrazzak,V Mladenovic,P.D Tung,M Petkovic,S Antipov

doi:10.1051/e3sconf/202127901011

Abstract

In this work, the hypothesis of taking into account a specific thermoEMF to determine the degree of hardening of the cutting tool by cryogenic hardening is put forward, which is the most convenient and important value from the point of view of information content. As a result of studies of improving the mechanical characteristics of instrumental materials by cryogenic treatment, the values of the absolute and specific values of thermo emf were revealed depending on the temperature of three instrumental materials obtained by tarrying them together with platinum. The values of temperatures at the maximum values of the specific thermo emf, have been obtained. It was found that deep cooling of the metal increases the degree of ordering of its structure and increases the vibrational energy of the crystal lattice. The results of the study showed that the resistance of the cryogenic cutting tool increases by up to three times, this positively affects the energy efficiency of the use of such a tool in production. The reduction of energy costs is expressed in the reduction of kilowatt-hours associated with the costs of sharpening the tool and can reach up to 30% of the total amount of electricity consumed.

Highlights

Researchers [6] presented methods of hardening of cutting tools that are used for additional processing of ready-to-use tools, such as cryogenic treatment, which is not included in the list of recommended hardening methods [6]
Studies on the effect of cryogenic treatment on the durability of drills, carried out at the Vilnius plant, showed [8] that: 1) the processing of finished high-quality drills made of steels S6-5-2S and S18-0-1 with liquid nitrogen does not have a tangible effect on the wear of cutting elements; 2) the processing of finished high-speed drills made of S6-5-2S steel with liquid nitrogen does not significantly increase the durability of drills with defects in mechanical heat treatment
[8] shows that the liquid nitrogen treatment did not obtain any rigorous scientific hypothesis explaining the physical nature of the process of increased stamina resistance of a low temperature treated cutting tool

Summary

Introduction

Researchers [6] presented methods of hardening of cutting tools that are used for additional processing of ready-to-use tools, such as cryogenic treatment, which is not included in the list of recommended hardening methods [6]. On pages of technical literature there is no consensus on use of cryogenic processing (or "processing’s by cold", "processing’s by deep cold", "deep cooling", etc.) for increase in the cutting properties (hardening) of the cutting tool This method is explained by the fact that for most of them the point M, the end of martensitic transformations lies below 0 °C [1], and its position varies depending on the chemical composition of the steels in the range -55... Appropriate experimental studies of fast-cutting steel, hard alloys, and cutting ceramics WOK60 are needed, after cooling into a temperature in the vicinity of 195.8 °C, to find the optimal cryogenic temperature and explain the processes occurring in instrumental materials during cryogenic processing

Materials and Methods

Findings

Specific thermoEMF and Debye temperature