The phase I research is intended to demonstrate the basic feasibility of constructing and optimizing a new magneto-optic 'sandwich' device intended for direct visualization of flaws in ferrous materials (steel) in a marine environment. The device is based in the property of some magneto-optic garnet films to rotate the planes of polarization of an incident, linearly polarized light wave (Faraday magneto-optic effect). Such a device (in the 'sandwich' form) can be hand-held or operated by an automated submersible. Owing to the anticipated capability of such devices to observe the magnetic anomalies of flaws through considerable thickness of biofouling (up to 1/4 inch) this technique does not require clearing of surfaces before inspection. For these reasons, it should have considerable value as an inspection tool in a wide variety of marine environments, especially in floating offshore oil platforms and related inspection tool in a wide offshore oil platforms and related inspection problems. Res: the phase I research will demonstrate the feasibility of constructing magneto optic based flaw imaging devices in should be able to provide flaw images in steel directly, even through biofouling, the device is anticipated to have considerable commercial significance in marine inspection environments.
