Method and apparatus for separating magnetic field attributable to flaws in a material from magnetic fields attributable to other phenomena

US4628261A · kind A · utility

Assignee

• Nukem, LLC · DE

Inventors

• Gerhard Huschelrath · Laufach, DE
• Ursula Ruth · Ronneburg, DE

Key dates

• Filing date: Apr 5, 1983
• Grant date: Dec 9, 1986
• Expiry date: Apr 5, 2003

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/9046
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method and an apparatus for testing materials using the eddy current principle enables a better exploitation of the sensitivity of measurement. Initially, the complex values appearing during a test cycle are examined as to whether only disturbance signals, disturbance signals in connection with flaw signals, or only flaw signals are present. The complex values are selectively further processed directly if there are flaw signals only, or are further processed for disturbance signal elimination. The direct further processing as well as the further processing made after elimination of the disturbance signal comprises the determination of the type of flaw and the depth of the flaw.