§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
US4110236A Expired / Lapsed US ⏱️ 0.0 years remaining

Nondestructive magnetic recording medium

Assignee: Boeing North American Inc
•
Filing: 1976-04-19
•
Granted: 1978-08-29
•
Expires: 1996-04-19
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method for nondestructive magnetic particle inspection of an object or part, especially parts having complex configurations, for detection of defects and metallurgical conditions therein, by placing a novel magnetic recording medium in the form of a magnetizable preferably putty-like material on the surface of the object, magnetizing the object and such putty-like material in contact with the object, and recording on such magnetizable putty-like material, magnetic particle indications of such defects and metallurgical conditions, removing the so-magnetized putty-like material from the object, placing a viewing device on the area of the magnetized putty-like material previously in contact with the object, such device preferably being one containing a suspension of weakly ferromagnetic crystals in a transparent liquid vehicle, and having a transparent portion to permit viewing such suspension, and viewing through such device the outlines and indications of the defects and metallurgical conditions in the object, produced by the reorientation of the ferromagnetic particles of the suspension, and corresponding to the magnetic particle indications recorded on the magnetized putty-like material. A novel rubbery to putty-like magnetic recording medium is preferably in the form of a silicone polymer containing magnetic particles.

Inventors

  • 👤 Orlando G. Molina

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 17:19
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/10; H01F1/11; H01F1/113; H01F1/117; G; G01; G01N; G01N27/00; G01N27/72; G01N27/82; G01N27/83; G01N27/84; G01R; G01R33/00; G01R33/02; G01R33/10

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 128 words
A magnetizable putty-like recording medium for magnetic particle inspection of an object, comprising a material selected from the group of polymers and resins consisting essentially of silicone polymers, urethane polymers, natural rubber, neoprene, carboxyl terminated polybutadiene, and guar gum, said polymers and resins having a viscosity such that said polymers have putty-like characteristics, and including magnetic particles distributed therein, said material being highly pliable and moldable so that it can be applied to a part surface and pressed by light pressure against the surface to fill any gaps between the putty-like material and the surface of the part, said recording medium being demagnetizable following magnetization, and reuseable, said magnetic particles being present in an amount of about 5 to about 60%, by weight of said polymers and resins.
Claim 2
Dependent Claim 128 words
A magnetizable putty-like recording medium for magnetic particle inspection of an object, comprising a material selected from the group of polymers and resins consisting essentially of silicone polymers, urethane polymers, natural rubber, neoprene, carboxyl terminated polybutadiene, and guar gum, said polymers and resins having a viscosity such that said polymers have putty-like characteristics, and including magnetic particles distributed therein, said material being highly pliable and moldable so that it can be applied to a part surface and pressed by light pressure against the surface to fill any gaps between the putty-like material and the surface of the part, said recording medium being demagnetizable following magnetization, and reuseable, said magnetic particles being present in an amount of about 5 to about 60%, by weight of said polymers and resins.
Claim 3
Dependent Claim 17 words
A magnetizable recording medium as defined in claim 1, said material being a moldable putty-like silicone polymer.
Claim 4
Dependent Claim 16 words
A magnetizable recording medium as defined in claim 2, said silicone polymer being a dimethyl polysiloxane.
Claim 5
Dependent Claim 33 words
A magnetizable recording medium as defined in claim 3, said silicone polymer having a viscosity of about 100,000 centistokes and containing finely divided boric acid powder, and said magnetic particles being ferromagnetic particles.
Claim 6
Dependent Claim 27 words
A magnetizable recording medium as defined in claim 3, said magnetic particles being magnetic oxides or ferromagnetic particles of a fine size of 325 mesh or smaller.

References Cited (Backward Citations)

US2601212A Cited
US2744040A Cited
US2849312A Cited
US3029157A Cited
US3470021A Cited
US3384498A Cited
US3740266A Cited
US3681137A Cited
US3862047A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-08-28 1982-02-27 1982-08-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-08-28 1986-02-27 1986-08-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-08-28 1990-02-27 1990-08-29 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag