Title:
【発明の名称】ホログラフィー干渉方法を用いる構造試験
Document Type and Number:
Japanese Patent JPH06504121
Kind Code:
A
Abstract:
PCT No. PCT/AU91/00595 Sec. 371 Date Jun. 18, 1993 Sec. 102(e) Date Jun. 18, 1993 PCT Filed Dec. 20, 1991 PCT Pub. No. WO92/11506 PCT Pub. Date Jul. 9, 1992.In-situ, nondestructive examination to test the efficacy of a riveted, bolted or bonded join of metal sheets, or to test whether a composite material is faulted, or to test whether a multi-layer patch is bonded properly, involves the creation of an interferometric hologram. A photographic film or plate is mounted closely above, and isolated vibrationally from a region of a structure containing the join, composite material or patch. The film or plate is illuminated by the expanded beam from a laser firstly when the structure is in a first state of stress, and secondly when the structure is in a second state of stress (the change in stress being sufficient to deform the region over which the film or plate is mounted). At each illumination, a diffraction pattern is produced in the emulsion of the plate or film by interference between the illuminating beam and that part of it which is reflected from the region. The two diffraction patterns combine to produce a fringe pattern in the emulsion. That fringe pattern, when compared with the fringe pattern produced by a good join or a non-faulted composite body of patch, provides information about the region under investigation. The technique is especially useful for testing the joins in the skin of an aircraft fuselage, or potentially damaged composite structures.
Inventors:
Bird, John Patrick
Clark, Robert Case
Clark, Robert Case
Application Number:
JP50161992A
Publication Date:
May 12, 1994
Filing Date:
December 20, 1991
Export Citation:
Assignee:
UNISEARCH LIMITED
International Classes:
G01B9/021; G01B11/16; G01M99/00; G01M11/00; G01N21/84; (IPC1-7): G01M19/00; G01M11/00; G01N21/84
Domestic Patent References:
| JPS54148082A | 1979-11-19 | |||
| JPH01192551A | 1989-08-02 | |||
| JP1113886B |
Foreign References:
| US3822107A | 1974-07-02 | |||
| US4302416A | 1981-11-24 |
Attorney, Agent or Firm:
Aoyama Ryo (2 outside people)