Patent · US Expired

Rapid carburizing process in a continuous furnace

US4769090A · kind A · utility

4Cited by
8References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 10, 1986
Grant dateSep 6, 1988
Priority date
Expiry dateJul 10, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC23C8/22
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

Process in which there are injected a carrier gas and a hydrocarbon capable of producing, at conventional carburizing temperatures, an atmosphere of predetermined composition having a nominal concentration of carbon monoxide, a door of the furnace being opened with a given periodicity to permit the passage of a charge to be carburized, the opening of this door resulting in particular in an increase in the concentration of the oxidizing species in the atmosphere of the furnace. According to the invention, the concentration of carbon monoxide of the atmosphere injected into the furnace is increased with the same periodicity so as to compensate for the increase in the concentration of the oxidizing species of the furnace and thus maintain the carbon potential of the carburizing atmosphere of the furnace substantially constant throughout the duration of the carburization of the workpieces of the charge.

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