Structural Defects in TiNi-Based Alloys after Warm ECAP
| Parent link: | Metals Vol. 10, iss. 9.— 2020.— [1154, 11p.] |
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| Other Authors: | , , , , |
| Summary: | Title screen The microstructure, martensitic transformations and crystal structure defects in the Ti50Ni47.3Fe2.7 (at%) alloy after equal-channel angular pressing (ECAP, angle 90°, route BC, 1–3 passes at T = 723 K) have been investigated. A homogeneous submicrocrystalline (SMC) structure (grains/subgrains about 300 nm) is observed after 3 ECAP passes. Crystal structure defects in the Ti49.4Ni50.6 (at%) alloy (8 ECAP passes, angle 120°, BC route, T = 723 K, grains/subgrains about 300 nm) and Ti50Ni47.3Fe2.7 (at%) alloy with SMC B2 structures after ECAP were studied by positron lifetime spectroscopy at the room temperature. The single component with the positron lifetime t1 = 132 ps and t1 = 140 ps were observed for positron lifetime spectra (PLS) obtained from ternary and binary, correspondingly, annealed alloys with coarse-grained structures. This t1 values correspond to the lifetime of delocalized positrons in defect-free B2 phase. The two component PLS were found for all samples exposed by ECAP. The component with t2 = 160 ps (annihilation of positrons trapped by dislocations) is observed for all samples after 1–8 ECAP passes. The component with t3 = 305 ps (annihilation of positrons trapped by vacancy nanoclusters) was detected only after the first ECAP pass. The component with t3 = 200 ps (annihilation of positrons trapped by vacancies in the Ti sublattice of B2 structure) is observed for all samples after 3–8 ECAP passes. |
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2020
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| Online Access: | http://earchive.tpu.ru/handle/11683/64780 https://doi.org/10.3390/met10091154 |
| Format: | Electronic Book Chapter |
| KOHA link: | https://koha.lib.tpu.ru/cgi-bin/koha/opac-detail.pl?biblionumber=662889 |