Study of the stress-strain and temperature fields in cutting tools using laser interferometry

OBRABOTKAMETALLOV Vol. 23 No. 3 2021 MATERIAL SCIENCE EQUIPMENT. INSTRUMENTS 4 Study of the stress-strain and temperature fi elds in cutting tools using laser interferometry Igor E fi movich a,* , Ivan Zolotukhin b Tyumen Industrial University, 38 Volodarskogo, Tyumen, 625000, Russian Federation a https://orcid.org/0000-0002-9060-4988, egor_kosin@mail.ru, b https://orcid.org/0000-0002-1517-9117 , zolotuhinis@tyuiu.ru Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2021 vol. 23 no. 4 pp. 79–92 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2021-23.4-79-92 Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov ARTICLE INFO Article history : Received: 13 September 2021 Revised: 28 September 2021 Accepted: 09 November 2021 Available online: 15 December 2021 Keywords : Metal cutting Metal cutting tool Strain measurement Laser interferometry High-speed video recording Stress-strain state Stress distribution Temperature distribution Temperature fi eld Boundary condition Numerical analysis ABSTRACT Introduction . The ef fi ciency of the metalworking processes highly depends on the performance of the implemented cutting tools that can be increased by studying its stress-strain state and temperature fi elds. Existing stress analysis methods either have a low accuracy or are inapplicable for research during the operation of the tools made of materials with high mechanical properties. In addition, the study of temperature fi elds using known methods is dif fi cult due to the small size of the cutting zone, high temperatures, and a heavy temperature gradient appearing during metal cutting. The purpose of this study is to develop new experimental methods for measuring the stress- strain and temperature fi elds in the cutting tool during its operation using laser interferometry. The methods include: obtaining interference fringe patterns using an interferometer with the original design, obtaining the tool deformation fi eld during the cutting process by recording the changes in interference fringe patterns using a high-speed camera, processing fringe patterns with the separation of deformations caused by heating and cutting forces, and calculating temperature fi elds and stress distributions using mechanical properties and the coef fi cient of thermal expansion of the tool material. The advantages of the developed methods include: applicability under real operating conditions of the cutting tool, ability to study the non-stationary stress-strain state and temperatures during an operation, and achievement of a high spatial resolution and a small fi eld of view for the investigated surface. Results and Discussion. The experimental study con fi rmed the ef fi ciency of the methods. The results of the study included the fi elds of stresses and temperatures obtained during the orthogonal cutting of heat-resistant steel with a tool made of cemented tungsten carbide WC-8Co . The developed methods can be used to study the cutting tool ef fi ciency at close to real conditions and in obtaining boundary conditions for the study stress-strain state of a workpiece material near the cutting zone. For citation: E fi movich I.A., Zolotukhin I.S. Study of the stress-strain and temperature fi elds in cutting tools using laser interferometry. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2021, vol. 23, no. 4, pp. 79–92. DOI: 10.17212/1994-6309-2021-23.4-79-92. (In Russian). ______ * Corresponding author E fi movich Igor A. , Ph.D. (Engineering), Associate Professor Tyumen Industrial University 38 Volodarskogo, 625000, Tyumen, Russian Federation Tel.: +7 (3452) 50-49-15, e-mail: egor_kosin@mail.ru Introduction Cutting tool ef fi ciency largely determines the economic effectiveness of the technology in which the tool is used. Therefore, studying the stress-strain and temperature states of cutting tool in conditions that are as realistic as possible will allow cutting tool ef fi ciency to be improved. Many methods exist for studying the stress-strain state of solids, but each has features that limit its application to the problem of studying the stress-strain state of cutting tool. For example, using tensometers or strain gauges to study deformation fi elds is very dif fi cult because of the small dimensions of the zone under investigation in cutting tools and the high operating temperatures involved during their operation. The split tool method [1] enables study the cutting process under real conditions, but the peculiarities of the cutter design [2] distort the obtained results.