2025-03-27https://repository.covenantuniversity.edu.ng/handle/123456789/34068High·Tc superconductor quantum interference devices (SQUIDs) for noise-free, accurate measurements of defects and flaws in metal shapes and forms by measuring changes in the secondary magnetic field intensity around any point which is excited by a primary excitation current or by measuring changes in the impedance of the exciting coils. These measured changes are corre-· lated to defects and flaws present in the metal.application/pdfQ Science (General), QC PhysicsPatent