Resources Contact Us Home
Nondestructive fatigue test method for ferromagnetic construction materials

Image Number 3 for United States Patent #6345534.

A nondestructive test method determines fatigue of a test ferromagnetic construction material by quantifying a change in effective stress due to aging of the test material, in which the magnetic susceptibility (.chi..sub.c) of the test material is measured in its aged state under a magnetic field having a specified intensity (H) according to a relation as expressed by a first equation: c=.chi..sub.c H.sup.3. The magnetic susceptibility (.chi..sub.c) so measured and the magnetic field intensity (H) are put into the first equation, to obtain a susceptibility coefficient (c) of the test material. The susceptibility coefficient (c) so obtained is put into a second equation: .sigma.={log (c)-a}/b, where a and b are known constants determined by an internal structure of the test material, to obtain a current tensile stress (.sigma.) of the test material. The current tensile stress (.sigma.) of the test material so obtained is compared with a known, initial tensile stress (.sigma..sub.0) of the same test material, to determine a change in effective tensile stress of the test material.

  Recently Added Patents
Modified binding proteins inhibiting the VEGF-A receptor interaction
Plants and seeds of corn variety CV294874
Information obtaining and notification, data message forwarding and handover method and access node
Rechargeable battery
Pyrazole kinase modulators and methods of use
Managing job execution
Method for switching between virtualized and non-virtualized system operation
  Randomly Featured Patents
Method and system for policy-based protection of application data
Adding positional information for surfaces in a geological formation after transforming to a gapped representation
Video and audio data multiplexing into ATM cells with no dummy cell used and ATM cell demultiplexing
Electronic component, semiconductor device, methods of manufacturing the same, circuit board, and electronic instrument
Shoe upper
Axial piston machine
Integrated devices and systems for performing temperature controlled reactions and analyses
Clay-based sulfur sorbent
Animated display calibration method and apparatus
Vehicle warning system