Precision nondestructive testing of metals

Details Precision nondestructive testing of metals Precision nondestructive testing of metals

1983-05-31

1987-05-19

Eisenzopf, Reinhard J.

Electricity: measuring and testing

Conductor identification or location

Inaccessible

324 62, G01R 2714

Patent

active

046671498

ABSTRACT:
A large number of applications exists for measuring the resistivity or other properties of ferrous and nonferrous metals, including matching alloys to ensure weld compatibility and measuring weld size to estimate weld strength. In the present invention, a DC current-reversal technique allows for accurate electrical measurement with a 4-point probe, alleviating problems due to surface potentials, thermal effects, and eddy currents that previously rendered such measurements inaccurate. Estimates of thermal conductivity, flaw size and location, among others, can also be obtained.

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