Grain boundary engineering of polycrystalline shape memory alloys by phase manipulation for enhanced mechanical ductility and application fatigue life
US10801094B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 2015 |
| Grant date | Oct 13, 2020 |
| Priority date | — |
| Expiry date | May 21, 2036 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D2211/008
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Provided is a method of making a polycrystalline shape memory alloy (SMA) by forming an alloy with grains and boundaries between them, exposing the alloy to a two-phase temperature range at which a two-phase equilibrium is achieved in the alloy, converting grains to an austenite phase, and precipitating a face-centered-cubic crystal structure solid solution phase at grain boundaries, then quenching the alloy. Also provided is a polycrystalline SMA with a dual-phase microstructure having grains mostly in an austenite phase, a martensite phase, or in transition between an austenite phase and a martensite phase and grain boundaries containing a face-centered-cubic crystal structure solid solution phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.