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