Obrabotka Metallov. 2016 no. 2(71)

ОБРАБОТКА МЕТАЛЛОВ № 2 (71) 2016 93 МАТЕРИАЛОВЕДЕНИЕ OBRABOTKAMETALLOV (METAL WORKING AND MATERIAL SCIENCE) N 2 (71), April – June 2016, Pages 87–94 Thermal expansion of Al–Cu alloys after conditioning and heat treatment Afanas’ev V.K., D.Sc. (Engineering), Professor, e-mail: sv_dolgov@mail.ru Malyuh M.A., Junior researcher, e-mail: malyuh_ma@umu.sibsiu.ru Popova M.V. , D.Sc. (Engineering), Associate Professor, e-mail: m.popova@rdtc.ru Leis V. A., Junior researcher Dolgova S.V., Junior researcher, e-mail: sv_dolgov@mail.ru Siberian State Industrial University, 42 Kirov st., Novokuznetsk, 654007, Russian Federation Abstract There is a huge amount of works on the study of the invar effect including alloying of iron-nickel bases by all the available elements of the periodic table, including precious metals ( Pt, Pd ). However, the secret of the invar effect is still not clear. The effect of copper on the linear expansion of commercial purity aluminum A7 was studied previously. The results obtained led to the conclusion that it can be reasonable to use copper to produce light alloys with controlled thermal expansion. The mechanism of the thermal expansion of as-cast and deformed Al-Cu alloys depends on the melt conditioning and heat treatment. The melt conditioning is presented by the water steam purging. It is found that the melt conditioning leads to anomalies, which are reflected in the reduction of thermal expansion of the alloys of interest. Further heat treatment leads to the development of anomalies. It is shown that the hot plastic deformation significantly affect the temperature coefficient of linear expansion (TCLE, α) aluminum-copper alloys and the effect increases with copper content increasing. The possibility of application of the discovered mechanism to create a new invar alloys, differing by a low specific weight and lower cost is investigated. Keywords temperature coefficient of linear expansion, Al-Cu alloys, Invar, melt conditioning, heat treatment, anomaly of TCLE DOI: 10.17212/1994-6309-2016-2-87-94 References 1. Batyshev A.I., Smol’kin A.A., eds. Materialovedenie i tekhnologiya materialov [ Materials science and tech- nology of materials ] . Moscow, Infra-M Publ., 2012. 288 p. ISBN 978-5-16-004821-5 2. Novikova S.I. Teplovoe rasshirenie tverdykh tel [ Thermal expansion of solid bodies ] . Moscow, Nauka Publ., 1974. 424 p. 3. Greenwood N.N., Earnshaw A. Chemistry of the Elements . 2 nd ed. Oxford, Boston, Butterworth-Heinemann Publ., 1997. 1600 p. ISBN-10: 0-7506-3365-4. ISBN-13: 978-0-7506-3365-9 (Russ. ed.: Grinvud N., Ernsho A. Khimiya elementov. V 2 t. T. 2. Translated from English. Moscow, BINOM. Laboratoriya znanii Publ., 2008. 670 p. ISBN 978-5-94774-372-2. ISBN 978-5-94774-374-6). 4. Kikoin I.K., ed. Tablitsy fizicheskikh velichin [ Tables of physical quantities ] . Moscow, Atomizdat Publ., 1976. 1006 p. 5. Molotilov B.V., ed. Pretsizionnye splavy [ Precision alloys ] . 2 nd ed. Moscow, Metallurgiya Publ., 1983. 439 p. 6. Kablov E.N. Strategicheskie napravleniya razvitiya materialov i tekhnologii ikh pererabotki na period do 2030 goda [ Strategical areas of developing materials and their processing technologies for the period up to 2030 ] . Aviatsi- onnye materialy i tekhnologii – Aviation materials and technologies , 2012, no. S (Special iss.), pp. 7–17. 7. Afanasev V.K., Gorshenin A.V., Starostina M.A., Pervakova E.V., Degtyaryova I.V. Vliyanie medi na lineinoe rasshirenie alyuminiya A7 [ Features of influence of copper on linear expansion of aluminium А7 ] . Metallurgiya mashinostroeniya – Metallurgy of Machinery Building , 2010, no. 3, pp. 30–34. 8. Afanasiev V.K., Gorshenin A.V., Рopova M.V., Prudnikov A.N., Starostinа M.A. O vliyanii kremniya na teplo- voe rasshirenie alyuminiya [ About influence of silicon on thermal expansion of aluminium ] . Metallurgiya mashi- nostroeniya – Metallurgy of Machinery Building , 2010, no. 6, pp. 23–26.