US3791198A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Testing panel for inspection penetrants having cracks of controlled depth and width
Assignee: Individual
•
Filing: 1972-11-27
•
Granted: 1974-02-12
•
Expires: 1992-11-27
Abstract
Abstract A test panel which may be used for evaluating inspection penetrant crack detection performance, comprising essentially a soft, malleable metal substrate coated with a brittle surface layer of controlled thickness within the range of from about 5 microns to 50 microns, said brittle layer having a pattern of craze cracks which are generated by a mechanical stretching of the panel to a point where the average crack width falls within the range of values from about 0.5 micron to 20 microns.
Inventors
- 👤 J Alburger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 23:53
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/91
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
94 words
In a test panel for evaluating inspection penetrant performance consisting essentially of a maleable metal sheet coated with a brittle surface layer capable of producing craze cracks under stress, the improvement wherein said brittle coating is controlled and adjusted to a thickness within the range of from about 5 microns to 50 microns, and said panel is mechanically stretched beyond the elastic limit of said maleable metal, whereby craze cracks are produced in said brittle layer, and controlled and adjusted to a width within the range of from about 1 micron to 20 microns.
Claim 2
Dependent Claim
94 words
In a test panel for evaluating inspection penetrant performance consisting essentially of a maleable metal sheet coated with a brittle surface layer capable of producing craze cracks under stress, the improvement wherein said brittle coating is controlled and adjusted to a thickness within the range of from about 5 microns to 50 microns, and said panel is mechanically stretched beyond the elastic limit of said maleable metal, whereby craze cracks are produced in said brittle layer, and controlled and adjusted to a width within the range of from about 1 micron to 20 microns.
Claim 3
Dependent Claim
25 words
A test panel in accordance with claim 1, in which said maleable metal sheet is aluminum, and said brittle surface layer is an anodic coating.
Claim 4
Dependent Claim
19 words
A test panel in accordance with claim 2, in which said anodic coating is stained with a visible-color dye.
Claim 5
Dependent Claim
22 words
A test panel in accordance with claim 2, in which said anodic coating is coated with a thin layer of sodium silicate.
Claim 6
Dependent Claim
19 words
A test panel in accordance with claim 4, in which said layer of sodium silicate contains a visible-color dye.
References Cited (Backward Citations)
US2186014A
Cited
US3164006A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |