Dynamic Precipitation Behavior of Secondary M7C3 Carbides in Ti-alloyed High Chromium Cast Iron
2013 (English)In: ISIJ International, ISSN 0915-1559, Vol. 53, no 7, 1237-1244 p.Article in journal (Refereed) Published
In-situ observations on the dynamic precipitation behavior of secondary carbides in Ti-alloyed High Chromium Cast Iron (HCCI) were performed by using a Confocal Laser Scanning Microscope (CLSM). Moreover, the detailed characterization of the microstructure before and after heat treatment was performed by using scanning electron microscopy (SEM). The secondary carbides, which precipitate from the matrix during heat treatment, were identified as M7C3 type carbides by using transmission electron microscopy (TEM). The number, size and volume of secondary carbides during heating, holding and cooling process were quantitatively evaluated based on the in-situ observation and SEM results. It was found that ferrite (alpha) and secondary carbides start to precipitate from the matrix at around 575 degrees C and 840 degrees C, respectively, during the heating process. In addition, the in-situ results showed that the number of secondary carbides increase with an increased heating temperature and time. Moreover, it was found that the size of these secondary carbides increase at higher temperatures and longer holding times. However, the number of secondary carbides increased with a decreased temperature. Finally, it was found that the volume fraction (similar to 5%) of secondary carbides was not changed to a large extent for the different heat treatment conditions being investigated.
Place, publisher, year, edition, pages
2013. Vol. 53, no 7, 1237-1244 p.
in-situ observation, CLSM, high chromium cast iron, secondary carbides, precipitation
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-126904DOI: 10.2355/isijinternational.53.1237ISI: 000322208600019ScopusID: 2-s2.0-84883239697OAI: oai:DiVA.org:kth-126904DiVA: diva2:643097
QC 201308262013-08-262013-08-222013-09-13Bibliographically approved