Obrabotka Metallov 2014 No. 3

ОБРАБОТКА МЕТАЛЛОВ № 3 (64) 2014 19 МАТЕРИАЛОВЕДЕНИЕ 8. Сварка трением с перемешиванием термиче- ски упрочняемого сплава В95 системы Al-Zn-Mg-Cu / В.А. Фролов, В.Ю. Конкевич, П.Ю. Предко, В.В. Бе- лоцерковец // Сварочное производство. – 2013. – № 3. – С. 21–26. 9. Schneider J.A., Nunes A.C. Characterization of Plastic Flow and Resulting Microtextures in a Friction Stir Weld // Metallurgical and Materials Transactions: B. – 2004. – Vol. 35, № 4. – P. 777–783. 10. Properties of Friction-Stir-Welded 7075 T651 Aluminum / M.W. Mahoney, C.G. Rhodes, J.G. Flint- off, R.A. Spurling and W.H. Bingel // Metallurgical and Materials Transactions: A. – 1998. – Vol. 29, iss. 7. – P. 1955–1964. 11. Rubtsov V.E., Tarasov S.Yu., Kolubaev A.V. One- dimensional model of inhomogeneous shear in sliding // Physical Mesomechanics. – 2012. – Vol. 15, № 5-6. – P. 337–341. 12. The Evolution of the Surface Layers on Met- als in Sliding Friction / A.V. Kolubaev, S.Yu. Tarasov, O.V. Sizova, E.A. Kolubaev, and Yu.F. Ivanov // Jour- nal of Friction and Wear. – 2007. – Vol. 28, № 6. – P. 514–520. 13. Павлова В.И., Алиференко Е.А., Осокин Е.П. Исследование температурно-временных условий сварочного нагрева, структуры и свойств металла стыковых соединений из алюминиево-магниевого сплава, выполненных сваркой трением с перемеши- ванием // Вопросы материаловедения. – 2009. – Т. 60, № 4. – С. 74–88. 14. Повышение надежности сварных соединений из высокопрочного алюминиево-литиевого спла- ва В-1461 / В.И. Лукин, Е.Н. Иода, А.В. Базескин, В.П. Лавренчук, Л.В. Котельникова, М.С. Оглодков // Сварочное производство. – 2010. – № 11. – С. 14–17. 15. Исследование массопереноса при триболо- гическом взаимодействии легированных сталей / Н.Б. Пугачева, С.В. Павлышко, Е.Б. Трушина, А.Н. Замятин // Трение и износ. – 2012. – Т. 33, № 3. – С. 265–274. OBRABOTKAMETALLOV (METAL WORKING AND MATERIAL SCIENCE) N 3(64), July – September 2014, Pages 14–20 Fracture of friction stir welded butt joints structure of aluminum-magnesium alloy Sizova O.V. 1, 2 , D.Sc. (Engineering), Professor, e-mail: ovs@ispms.ru Kolubaev A.V. 1, 2 , D.Sc. (Physics and Mathematics), Professor, e-mail: kav@ispms.ru Kolubaev E.A. 1, 2 , Ph.D. (Physics and Mathematics), e-mail: eak@ispms.ru Zaikina A.A. 1 , Post-graduate Student, e-mail: aaz@ispms.ru Rubtsov V.E. 1 , Ph.D. (Physics and Mathematics), e-mail: rvy@ispms.ru Institute of Strength Physics and Materials Science of the Siberian Branch of the RAS, 2/4 Academichesky ave., Tomsk, 634021, Russian Federation National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk, 634050, Russian Federation Abstract The results of aluminum-magnesium alloy friction stir welded joints fracture investigations are put forward in the article. Through the example of welded joints of plates with different thickness it is illustrated that macro- and microstructure of the welds have both common features of strained metal and peculiars caused by the impact of welding temperature-time criteria. It is demonstrated that the significant difference between weld microstructure and original metal was formation of the gradient fine-grained microstructure without signs of texture. It is revealed that as a result of heating and cooling temperature-time terms variation during welding of thick alloyed plates in the weld zone along with dynamic cell formation partial strained structure recrystallization can occur. It is illustrated that in case of recrystallization the joint fracture was along the boundary of the areas with different structures. A comparative analysis of the fracture topography of the broken specimen joints that were obtained from the alloy plates with different thickness is carried out. This analysis revealed that both cases showed similar fracture pattern. A crack originated in the root and run to a distance that is approximately equal to middle of the specimen gauge along to transition boundary of the base metal structure to gradient one. “Pest” degradation goes further. Nature of the alloy structuring mechanism in the weld zone stimulated with heating and intensive plastic deformation is discussed. Keywords: friction stir welding, aluminum alloy, microstructure, recrystallization, static tension, fracture.