Patent · US Expired

Method and apparatus for determining diffusible hydrogen concentrations

US7306951B1 · kind B1 · utility

19Cited by
23References
45Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 8, 2000
Grant dateDec 11, 2007
Priority date
Expiry dateOct 17, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T436/22
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A measuring apparatus and method for use in measuring diffusible hydrogen concentrations in materials, structures, and other objects. In an embodiment of the invention for use in welding applications, the measuring apparatus (10) includes a sensor assembly (20) that, with an included sealing member (40), defines a sample area (17) on a weld bead (16) from which hydrogen evolves into a sample volume (18) defined by the sealing member (40), a sensor housing (34) and a sensor (22) of the sensor assembly (20). The hydrogen reacts with a sensing layer (28) and a reflector layer (30) positioned on the end of an optical fiber (24), all of which are included in the sensor assembly (20) and are sealably positioned within the sensor (22). The sensing layer (28) comprises a chemochromic material that undergoes changes in physical properties, such as optical transmission properties, when it reacts with hydrogen and these changes are measured by the measuring apparatus (10) to determine the amount of hydrogen evolving from the sample area (17). An optical fiber (46) is joined to the sensor optical fiber (24) to direct light (63) transmitted by a light source (62) in a hydrogen monitoring assemb…

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