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Enhancement of Cu nano-precipitation by Al addition in a Cu-Ni bearing low alloy steel
X.Q. Rong,Hui Guo,Masato Enomoto,Chengjia Shang
Abstract The effect of Al addition on the evolution of Cu precipitates in an Fe-2Cu-1.5Mn-1.5Ni alloy during tempering at 500 °C was investigated. The atomic-scale characterization revealed that the Al addition enhanced Cu nucleation in the matrix and on dislocations (or PAGB). Furthermore, the dislocation density was greater in steel with Al, probably because a larger number of Cu particles delayed the recovery and annihilation of dislocations in the martensite matrix, which resulted in a significant increase of hardness after tempering. The concentrations of Cu and Mn in Cu clusters were lower and those of Al and Ni were higher than the values of both metastable equilibrium bcc-Cu and equilibrium fcc-Cu phases.
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“Enhancement of Cu nano-precipitation by Al addition in a Cu-Ni bearing low alloy steel” is a paper by X.Q. Rong Hui Guo Masato Enomoto Chengjia Shang published in the journal Materials Letters in 2021. It was published by Elsevier. It has an Open Access status of “closed”. You can read and download a PDF Full Text of this paper here.