Patent · US Expired

Memory element

US4777799A · kind A · utility

16Cited by
12References
48Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 2, 1987
Grant dateOct 18, 1988
Priority date
Expiry dateOct 2, 2007

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21D2201/01
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A memory element made of a shape-memory alloy includes lead-attachment and shape-memory portions and a partition interconnecting such portions. The lead-attachment and shape-memory portions are comprised of characteristic internal structures, while the partition is comprised of an internal structure dissimilar to the characteristic internal structure of at least one of the lead-attachment and shape-memory portions. Shape-memory effect characteristics of the shape-memory portion are preserved to maintain the memory function of the memory element by configuring the dissimilar internal structure to block transmigration from the lead-attachment to the shape-memory portions of selected contaminant material existing in the lead-attachment portion. The partition functions as a contaminant filter to control the concentration of contaminant material in the shape-memory portion, thereby enhancing the durability of the memory element. A method is disclosed of altering the first crystalline structure of an uncontaminated memory element to provide the dissimilar, contaminant migration-blocking, internal structure.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.