Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
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
Method and apparatus for band switching in wireless local access network
Device in a system operating with CAN-protocol and in a control and/or supervision system
Method and apparatus for sharing virtual workspaces
Clothes hanger
Method and apparatus for secure transfer and playback of multimedia content
Data converter with configurable functions
Signal processor and signal processing method
  Randomly Featured Patents
Information processing apparatus, information processing method, recording medium and program
Positioning system
Transformer for use in a static inverter
Improved coupling link
Retractable barrier strip
Multiple label container
Ship weight cargo loading and unloading system
Intelligent outdoor sun shading device
Tree dech
ORVR compatible refueling system