Dan DeVries of Criterion NDT Inc., Auburn, Wash., presented “Advances in Eddy Current Verification of Heat Treat Processes” at Heat Treat 2013 in Indianapolis last month. The latest generation of eddy current test instruments and probes enables manufactures to perform 100% in-line inspection of heat-treated components, thus reducing warranty, scrap, and testing costs.
The implementation of multi-frequency testing in conjunction with simplified user interfaces, allows these manufacturers to quickly create tests that effectively reject components with metallurgical defects such as misplaced case, shallow case, short quench, or ground out condition. In a study with a major powder metal gear manufacturer, eddy current testing showed a higher consistency of results versus Rockwell hardness (HrB) testing.
