Journals →  Tsvetnye Metally →  2021 →  #5 →  Back

ArticleName Experimental evaluation of the curves of maximal ductility and fluidity for titanium alloys in hot torsion testing
DOI 10.17580/tsm.2021.05.09
ArticleAuthor Medvedev M. I., Frolov Ya. V., Andreev A. V., Bobukh A. S.

National Metallurgical Academy of Ukraine, Dnipro, Ukraine:

M. I. Medvedev, Senior Researcher, Chair for Metal Forming, Doctor of Тechnical Sciences, e-mail:
Ya. V. Frolov, Professor, Нead of the Сhair for Metal Forming, Doctor of Тechnical Sciences, e-mail:

A. S. Bobukh, Associate Professor of the Chair for Metal Forming, Candidate of Тechnical Sciences, e-mail:


INTERTIPE Ukraine Ltd., Dnipro, Ukraine:
A. V. Andreev, Leading Specialist of the Department for Development of New Products and Technologies, Candidate of Тechnical Sciences, e-maill:


The purpose of this work is to clarify the temperature-deformation modes of extrusion pipes of titanium alloys (VT1-0, PT-7M, VT-14, VT-15, TS-5 and TS-6) and to determine the regression coefficients of the Hansel-Spittel equation by investigating plasticity and the deformation resistance during hot rotation of the specimens. This method using the torque, obtained at test procedures, makes it possible to get a complete picture of the metal flow developing in conditions of prevailing shear deformation. The shear strain, calculated from torque curves, is used as an indicator of transition to plastic area and consequent failure The hot-torsion tests were performed on a testing machine SMEG-10Т (torsion machine of the horizontal type with a maximum torque 100 Nm, equipped with a heating chamber). The temperature of the samples during the tests was in range of 800…1250 oС. Presented in this work results of hot-torsion experiments and its statistical processing are aimed to determine the regression coefficients of Hansel-Spittel equation which can be applied to calculation of parameters of seamless tubes extrusion for studied titanium alloys. Using specimens with a different ratio of radius to the length of the working part, were obtained the range of the strain rates from 6 to 25 s–1. The sensibility to strain rate at hot deformation was studied. It was found that it falls at temperatures of maximal duration of ductile behavior for majority of studied titanium alloys, excepting VT15 and PT7-M. The main results of the study should be considered experimentally determined curves of the torque dependence on the angle of rotation of the sample to change the resistance of deformation of the metal, which allowed to clarify the temperature interval of maximum ductility during pressure treatment for alloys VT1-0, PT-7M, VT-14, VT-15, TS-5 and TS-6.

keywords Titanium, deformation, pipe, temperature, torque, strain resistance, strain rate, extrusion

1. Danchenko V. N., Frolov Ia. V., Dekhtyarev V. S., Golovchenko A. P., Belikov Yu. M. et al. Development of Pipe Cold Pilger Rolling Mode Computation Method with Account of Metal Properties Change. Metallurgical and Mining Industry. 2011. Vol. 3. No. 3. pp. 110–113.
2. Andreiev A., Golovko O., Frolov Ia., Nurnberger F., Wolf La et al. Testing of pipe sections. Materials Testing. 2015. Vol. 57, No. 7-8. pp. 643–648.
3. Zhang W., Dinga H., Zhao J. et al. Hot deformation behavior and processing maps of Ti – 6Al – 4V alloy with starting fully lamellar structure. Journal of Materials Research. 2018. Vol. 33, Iss. 22. pp. 3677–3688.
4. Tang H., Yang M., Meng W., Lan P., Wang Ch. Hot deformation behaviour and microstructure of a high-alloy gear steel. Materials Science and Technology. 2018. Vol. 34. pp. 1228–1238.
5. Gubkin S. I. Plastic deformation of metals: in 3 vol. Moscow : Metallurgizdat, 1961.
6. Illarionov А. G., Popov А. А. Technological and operational properties of titanium alloys. Yekaterinburg : Izdatelstvo Uralskogo universiteta, 2014. 137 p.
7. Pernis R., Bidulská J., Kvakaj T., Pokorný I. Application of the torsion test in calculating the extrusion force. Archives of Metallurgy and materials. 2011. Vol. 56. pp. 81–85.
8. Pintãoa C. A. F., Correac D., Grandinib C. Torsion modulus as a tool to evaluate the role of thermo-mechanical treatment and composition of dental Ti – Zr alloys. Journal of Materials Research and Technology. 2019. Vol. 8, Iss. 5. pp. 4631–4661.
9. Pintão C., Correa D., Grandini C. Torsion modulus using the technique of mechanical spectroscopy in biomaterials. Journal of Mechanical Science and Technology. 2017. Vol. 31, Iss. 5. pp. 2203–2211.
10. Kolmogorov V. L. Plasticity and fracture. Moscow : Metallurgiya, 1977. 336 p.
11. Nadai А. Plasticity and fracture of solids. Moscow : Mir, 1969. 863 p.
12. OST 1.90013–81. Titanium alloys. Grades. Introduced: 01.07.1981.
13. TU 1-5-127–73. Pipe billet from titanium alloys. Introduced: 01.01.1974.
14. GOST 19807–91. Wrought titanium and titanium alloys. Grades. Introduced: 01.07.1992.
15. Medvedev М. I. Deformability of metals at hot pressing of pipes: Dissertation … of Candidate of Engineering Sciences. Dnepropetrovsk, 1974. 205.
16. Yang L. H., Wu L. Z. Determination of hardening coefficient of large strain constitutive model based on torsion tests. Advanced materials research. 2011. Vol. 197-198. P. 1528–1531.
17. Sclomchak G. G. Rheological concept in the theory of metal rolling. Teoriya i Praktika Metallurgii. 2005. No. 3. pp. 39–43.
18. Spittel T., Spittel M. Ferrous Alloys. Vol. 2. New York : Springer, 2009. 800 p.
19. Bouchard P. O., Laurent T., Tollier L. Numerical modeling of self-pierce riveting — From riveting process modeling down to structural analysis. Journal of Materials Processing Technology. 2008. Vol. 202, Iss. 1-3. pp. 290–300.
20. Chenot J. L., Oñate E. Modelling of Metal Forming Processes. Proceedings of the Euromech 233 Colloquium, Sophia Antipolis, France, August 29–31, 1988.
21. Xin Hou, Zhanqiang Liu, Bing Wang et al. Stress-Strain Curves and Modified Material Constitutive Model for Ti – 6Al – 4V over the Wide Ranges of Strain Rate and Temperature. Materials. 2018. Vol. 11, Iss. 6. pp. 938.
22. Bogatov A. A., Panov E. I. Effect of Stress-strain State during Helical Rolling on Metal and Alloy Structure and Ductility. Metallurgist. 2013. Vol. 57, Iss. 5-6. pp. 434–441.
23. Gryts А., Dyya Kh., Bayor Т., Kalamozh М. Analysis of deformation and stresses distribution in process of rolling of magnesium alloy rods AZ31 on a three-roll screw mill. Innovative technologies in metallurgy and mechanical engineering: Proceedings of the VII International youth scientific and practical conference “Innovative technologies in metallurgy and mechanical engineering”, dedicated to the memory of Corresponding Member RAS, Honorary Doctor of UrFU V. L. Kolmogorov. (Yekaterinburg, 26–30 November 2013). Yekaterinburg : Izdatelstvo Uralskogo universiteta, 2014. pp. 338–341.
24. Hensel А., Spittel Т. Kraft- und Arbeitsbedarf bildsamer Formgebungsverfahren: reference book. Translated from Germany. Moscow : Metallurgiya, 1982. 360 p.
25. Medvedev М. I., Gulyaev Yu. G., Chukmasov S. А. Improvement of the pipes pressing process. Moscow : Metallurgiya, 1986. 151 p.
26. Golovko A. N., Rodman D., Nürnberger F., Schaper M., Frolov Ia., Beliaiev S. Investigation of the water-air cooling process of the thick- walled extruded profile made of alloy EN AW-6060 on the output table. Metallurgical and Mining Industry. 2012. Vol. 4, Iss. 2. pp. 66–74.
27. Lütjering G., Williams J. C., Gysler A. Microstructure and Mechanical Properties of Titanium Alloys. Microstructure and Properties of Materials. 2000. Vol. 2. pp. 1–77. DOI: 10.1142/9789812793959_0001.

Language of full-text russian
Full content Buy