Criterion NDT eddy current heat treat and material structure test systems provide a proven non-destructive method to identify changes in material conductivity and permeability compared to a known good part. Multi-frequency eddy current systems can test for conditions such as misplaced case, shallow case, short heat, short quench, delayed quench, and incorrect material or alloy mix.

Our eddy current test systems offer many benefits over traditional heat treat validation methods.  Unlike sample testing processes using cut, polish, etch, and visual inspection techniques, eddy current testing provides a clean, fast, and repeatable process that can perform in-line inspections of all parts produced.

We run our heat treat and material structure verifications as static tests.  A part is placed inside an eddy current coil (or set of coils), and a magnetic field is induced into the part under test.  The test response is compared to the response of a known good part.  If the part under test falls outside of customer established parameters, the eddy current test instrument will signal an alarm condition.

Our eddy current heat treat and material structure probes contain multiple coil windings. Standard probes contain windings that support a single channel test, while complex probes can test multiple locations at a time.
Instruments offered by Criterion NDT provide simultaneous multi-frequency testing capabilities to help identify multiple material structure differences.

Eddy current heat treat and material structure tests can be performed rapidly making the inspection easy to integrate into a production line. Other advantages include:

  • Instantaneous responses
  • Tests for multiple anomalies at once
  • Green technology requiring no chemicals or couplants
  • Reliable and reproducible results
  • Easy integration into production lines for 100% part inspection rates