Patent · US Expired

Hydrogen absorbing alloy powder and method for producing hydrogen absorbing alloy powder

US6274194A · kind A · utility

6Cited by
9References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 3, 1999
Grant dateAug 14, 2001
Priority date
Expiry dateFeb 3, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S420/90
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The present invention relates to a surface treatment for hydrogen-absorbing alloy. More particularly, the present invention relates to a surface treatment for hydrogen-absorbing alloy by which the poisoning resistance of a surface of alloy powder with respect to oxide film, water or absorbing gas can be enhanced so that activation treatment can be easily conducted on alloy powder. In the method, the poisoning resistance is enhanced by forming a protective film, which contains at least one of sulfide and fluoride, on the surface of hydrogen-absorbing alloy powder in an atmosphere containing SF.sub.6 gas when hydrogen-absorbing alloy is crushed or hydrogen-absorbing alloy is in a state of powder or when hydrogen-absorbing alloy is made into powder by rapidly cooling and solidifying. Further, the above method includes: a process in which hydrogen-absorbing alloy is accommodated in a container and crushing of hydrogenation is conducted on the alloy in an atmosphere of hydrogen; a process of dehydrogenation in which gases are withdrawn from the container; and a process in which heat treatment is conducted in the container, wherein the atmosphere in the container contains SF.sub.6 gas.

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