Magnetic nondestructive test for resistance spot welds using magnetic flux penetration and eddy current methods

Keiji Tsukada, Kousuke Miyake, Daichi Harada, Kenji Sakai, Toshihiko Kiwa

Research output: Contribution to journalArticle

12 Citations (Scopus)


Resistance spot welding technologies are widely used in industry. A highly reliable monitoring method is needed to effectively weld and create a robust structure. We developed a combined technique using magnetic flux penetration and an eddy current test (ECT). The magnetic measuring system consists of a pair of magnetic probes having an induction coil and detection coil, a lock-in amplifier, a current source, and a personal computer. The magnetic flux penetration through both surfaces at the weld was measured at low frequency. The ECT was performed at each surface with multiple frequencies. The magnetic flux penetration method showed good correlation with the destructive shear test because of the change in permeability due to the formation of the nugget. The ECT method reflected the depth profile of the nugget and was effective for determining a defective product.

Original languageEnglish
Pages (from-to)286-293
Number of pages8
JournalJournal of Nondestructive Evaluation
Issue number3
Publication statusPublished - Sep 2013



  • Eddy current test
  • Magnetic flux
  • Spot weld

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials

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