Junhe Li

Dr. Junhe Li

University of Science and Technology Beijing

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 November 2020 in Metals
Verified
Journal Article
Open access
PDF file
Junhe LiJunhe Li
Junhe Li
WSWei Shen
Wei Shen
PLPing Lin
Ping Lin
FWFuming Wang
Fuming Wang
ZYZhan-bing Yang
Zhan-bing Yang
The changes of microstructures, element distribution, and comprehensive properties were studied to explore their interactions with each other, induced by solution treatment of UNS S32750 super duplex stainless steel. The results showed that the ferrite content improved, while the austenite content declined as the temperature increased. From 900 to 1000 °C, the σ phase existing at α/γ grain boundaries and in ferrite grains gradually dissolved. At 1050 °C, the microstructures consisted of only ferrite and austenite. From 1050 to 1300 °C, the Cr2N precipitated in ferrite and gradually grew and coarsened. The impact energy and pitting potential of UNS S32750 first improved and then weakened, while the hardness is the opposite, owing to the combined effects of element distribution, microstructures, and precipitates. In the presence of the σ phase, the corrosion resistance and mechanical properties of UNS S32750 correspond directly to the σ phase fraction. Subsequently, the rise in temperature promoted γ → α phase transformation, and the elements partitioning ratios of Cr and Mo declined, resulting in reduced toughness and corrosion resistance and a rise in hardness. Consequently, when the solution treatment temperature is 1050 °C, the α/γ ratio of UNS S32750 approached 1:1, with excellent overall properties.