Formation of nanocrystalline structure in the amorphous Ti50Ni25Cu25 alloy upon severe thermomechanical treatment and the size effect of the thermoelastic martensitic B2 a dagger{''} B19 transformation / Pushin V. G.,Kuranova N. N.,Pushin A. V.,Valiev E. Z.,Kourov N. I.,Teplykh A. E.,Uksusnikov A. N. // PHYSICS OF METALS AND METALLOGRAPHY. - 2012. - V. 113, l. 3. - P. 271-282.

ISSN/EISSN:

0031-918X / нет данных

Type:

Article

Abstract:

The results of the comparative analysis of the Ti50Ni25Cu25-alloy structures produced in the initial amorphous state by rapid quenching from the melt (RQM), after severe plastic deformation by torsion under high pressure (HPT), and postdeformation heat treatment (PHT) are presented. The study was carried out using neutron and X-ray diffraction, transmission and scanning electron microscopy, and measurements of electrical properties. The initially amorphous alloy has been established to nanocrystallize after torsion under a pressure of 7 GPa to 0.5 revolutions of the anvil. Then, after 1, 5, 10, and 15 rev, the alloy again undergoes the strain-induced amorphization even with the retention, even after 5-15 rev, of a large number of highly dispersed nanocrystals less than 3-4 nm in size with a distorted B2 lattice in the amorphous matrix. Their crucial role as nuclei of crystallization provides the total low-temperature nanocrystallization during subsequent annealing starting from 250-300A degrees C. It is shown that PHT of the alloy amorphized by HPT makes it possible to produce extremely uniform nanocrystalline (NC), submicrocrystalline (SMC), or bimodal (NC + SMC) austenitic B2-type structures in it. A complete diagram of thermoelastic martensitic transformations in the region of B2-austenite states, from nanostructured state to conventional polycrystalline one, has been constructed. The size effect on the stabilization of martensitic transformation in nanocrystalline B2 alloy has been established.

Author keywords:

amorphous titanium nickelide; Ti50Ni25Cu25 alloy; high-pressure torsion; annealing; crystallization; recrystallization; martensitic diagram; size effect on thermoelastic martensitic transformations SEVERE PLASTIC-DEFORMATION; SHAPE-MEMORY ALLOYS; PHASE-TRANSFORMATIONS; TITANIUM NICKELIDE; TORSION; PRESSURE; FEATURES

DOI:

10.1134/S0031918X1203012X

Web of Science ID:

ISI:000301608900008

Соавторы в МНС:

Другие поля

Поле	Значение
Month	MAR
Publisher	MAIK NAUKA/INTERPERIODICA/SPRINGER
Address	233 SPRING ST, NEW YORK, NY 10013-1578 USA
Language	English
Keywords-Plus	SEVERE PLASTIC-DEFORMATION; SHAPE-MEMORY ALLOYS; PHASE-TRANSFORMATIONS; TITANIUM NICKELIDE; TORSION; PRESSURE; FEATURES
Research-Areas	Metallurgy \& Metallurgical Engineering
Web-of-Science-Categories	Metallurgy \& Metallurgical Engineering
ResearcherID-Numbers	Kuranova, Natalia/J-4368-2013 Vladimir, Pushin/J-4807-2013 kourov, Nikolai/J-9421-2013 valiev, eduard/J-9337-2013 Uksusnikov, Alexey/J-5270-2013
ORCID-Numbers	Kuranova, Natalia/0000-0002-5330-7909 Vladimir, Pushin/0000-0001-7569-0999 kourov, Nikolai/0000-0002-6104-9102 valiev, eduard/0000-0002-0760-0370 Uksusnikov, Alexey/0000-0003-2551-8968
Funding-Acknowledgement	Presidium of the Russian Academy of Sciences {[}09-P-2-1036]; Russian Foundation for Basic Research {[}11-02-00021]
Funding-Text	This work was supported in part by the Presidium of the Russian Academy of Sciences, project no. 09-P-2-1036, and by the Russian Foundation for Basic Research, project no. 11-02-00021.
Number-of-Cited-References	35
Usage-Count-Since-2013	10
Journal-ISO	Phys. Metals Metallogr.
Doc-Delivery-Number	910AF