Comprehensive presentation of the eddy current structure test and the physical basics, written by ibg founder Herbert Baumgartner for the second edition of the American “bible” of induction hardening “Handbook of Induction Heating” which will be published in 2015. Particular attention is given to the ibg inventions Preventive Multi-Frequency Technology (PMFT) and the new Simultaneous Harmonic Analysis iSHA.
Brief description of the ibg innovation Simultaneous Harmonic Analysis in eddy current testing. The iSHA technology (ibg’s Simultaneous Harmonic Analysis) enables a simultaneous calculation of the vectors of the fundamental wave and two harmonics of up to eight frequencies without extension of test time. It additionally uses high frequencies and their harmonics for a better solution of even the smallest structure differences. Thus iSHA greatly enlarges the possibilities of the well-known Preventive Multi-Frequency Technology (PMFT) for industrial applications. Text and poster were prepared for a short lecture at the DGZfP Annual Meeting in 2013.
A difﬁcult problem for in process inspection of mass parts is supervision of heat treatment results. Veriﬁcation of features like correct case depth and hardness are of prime importance for meeting the quality and safety of the ﬁnal product. In view of defects which violate statistical distribution laws, a possible solution is the non-destructive 100% test by using eddy current. The German article was published 1996 in the magazine Härterei-Technische Mitteilungen (HTM) and to date has not lost its relevance.
The English article is the sum-up of a lecture at the Heat Treat Show in Detroit, MI, in 2019.
It explains why a 100 % test by using the PMFT eddy current method on hardened parts provides a very high protection against unexpected hardness defects and material mix-up. Thus conclusions are possible with regard to case depth, hardness profile, carbon content, soft spots and other microstructural changes.
Application examples on camshafts, bolts, ball bearing balls, distance pins and special screws show the performance of the eddy current test on mass-produced products.
This article is the summary of a lecture at the International Induction Heating Seminar in Nashville TN in 1995. Among others it depicts the advantages of the Preventive Multi-Frequency Technology compared to the single-frequency structure test. It also includes a table of kinds of defects which may occur during the induction hardening process and take a closer look at applications like testing induction-hardened water pump shafts and steering racks.
Grinder burn during production is a risk for component reliability. Reference standards are necessary for assessment, setup and verification of appropriate test methods for grinder burn testing. They can be produced by means of laser burn. These defects have an analogous behaviour like real damages. They can be widely manufactured and reproduced at defined spots according to your requirements (kind and depth of structure change, special dimension). This lecture was a co-operation of imq Ingenieurbetrieb (Crimmitschau), Röntgenlabor Eigenmann (Schnaittach) and ibg Prüfcomputer (Ebermannstadt) for the Annual Meeting of DGZfP in 2012.
The eddy current test on many safety-critical components is a non-destructive 100%-end-of-line-test so the documentation of test data for traceability is naturally of high importance. For this, ibg as the first manufacturer worldwide has implemented a AQDEF-compliantly test data export in the digital eddy current test instruments eddyvisor / eddyliner. Test data are transferred after termination of each test part via Ethernet to a protocol computer where the ibg eddyQDAS software receives the data and provides them AQDEF-compliantly to the QS-STAT interface.