Abstract
In order to investigate the effects of Nb carbo-nitride precipitation conditions on abnormal grain growth behavior during high temperature carburizing, size of Nb carbo-nitride precipitates was controlled by precipitation treatment at 1173-1273K for 0.6-54ks, and the specimens were quasi-carburized at 1323K. Abnormal grain growth was enhanced when the size of Nb precipitates was fine or coarse, so there is a suitable size range in Nb precipitates to suppress abnormal grain growth. The reason why abnormal grain growth was enhanced is the lack of pinning force as the conventional theory proposed by Hillert or Gladman; however, it cannot be explained by this theory that small precipitates promote abnormal grain growth. It is considered that Ostwald ripening rate of precipitates is also an important factor in controlling abnormal grain growth in addition to the amount and size of precipitates and austenite grain size, which were parameters in the Gladman‘s theory on abnormal grain growth behavior.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.