Shape memory material and method of treating same
US4484955A · kind A · utility
Inventor
Key dates
| Filing date | Dec 12, 1983 |
| Grant date | Nov 27, 1984 |
| Priority date | — |
| Expiry date | Dec 12, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22F1/006
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of treating an integral piece of thermosensitive material which undergoes thermoelastic, martensitic phase transformation in response to heat to pass from a martensitic phase when at a temperature below a phase transformation temperature range and capable of a first high level of recoverable strain to a parent austenitic phase and memory shape when at a temperature above the phase transformation temperature range and capable of a second lower level of recoverable strain. The method is characterized by first cold working the material to a cold worked state comprising a disordered combination of martensitic and austenitic structures and then memory annealing a first portion of the integral piece of material to establish the martensitic and austenitic phases and the memory shape in the austenitic phase while retaining a second portion of the integral piece of material in the cold worked state and incapable of shape memory response. The piece of material is then mounted in a working environment by being supported and restrained in the second cold worked portion while the first annealed portion is free to pass back and forth between the martensitic and austenitic phases to prod…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.