Abstract
Jominy end-quench test samples from CF53 were used for studying the relationship of microstructural changes with the magnetic Barkhausen noise (BN) response.As the Barkhausen noise method is sensitive to both stress and microstructural state, it can be applied for material characterization. This study presents observations from BN measurements with different sensors and from different locations (as-quenched and ground) on the sample surface. Detailed microstructural characterization with a scanning electron microscope and a transmission electron microscope was carried out to correlate the BN responses with the microstructural features. In addition, residual stresses were measured by X-ray diffraction. The results indicate that the ground surface displayed mainly the effect of the grinding compressive stress state, while the as-quenched surface had variations due to higher microstructure sensitivity. An important finding of the results was that the sensitivity of BN to different surface conditions varied: The BN response in the ground area was mainly generated by both the residual stress and the microstructural effect, whereas for the as-quenched surface the microstructural effect was more evident.
Highlights
Jominy end-quench test in generalThe Jominy end-quench test is a standardized hardenability test for steels
This study presents observations from Barkhausen noise (BN) measurements with different sensors and from different locations on the sample surface
The surface hardness along the different measurement lines 1 and 2 from Jominy bars A, B and C is presented in Fig. 2a, b
Summary
The Jominy end-quench test is a standardized hardenability test for steels. Jominy tests are used to predict the depth of hardening and the so-called Jominy curves are utilized for characterizing the steel grade. Using Jominy tests, a comparison can be made of the hardenability, i.e., the ability to form martensite on the quenching of different steel grades. Hardenability is greatly affected by the chemical composition of the steel grade and the austenite grain size [2, 3]. Manganese, chromium or molybdenum, for example, enhances the stability of austenite and produces deep hardening by changing the time–temperature–transformation curves [3]. A similar effect can be observed when the austenite grain size is increased [2, 3]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
