Relationship between Laves phase and the impact brittleness of P92 steel reevaluated

Published on Jul 15, 2015in Materials Science and Engineering A-structural Materials Properties Microstructure and Processing4.652
· DOI :10.1016/J.MSEA.2015.05.012
Zhong Wanli2
Estimated H-index: 2
(EPRI: Electric Power Research Institute),
Wang Wei3
Estimated H-index: 3
(EPRI: Electric Power Research Institute)
+ 5 AuthorsKe Yang49
Estimated H-index: 49
(CAS: Chinese Academy of Sciences)
Sources
Abstract
Abstract Laves phase has been widely accepted to cause the impact brittleness of 9–12Cr martensitic heat-resistant steels after long time aging at elevated temperatures. However, in the present research, the impact toughness of the already brittle P92 steel aged at 600 °C for 2035 h could be restored to the original level by reheating at 700 °C for 1 h, with Laves phase barely changed. This interesting result strongly indicated that the presence of Laves phase might not be the real reason for the impact brittleness.
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