Open AccessPositron annihilation study of hot band of a continuous cast AA 2037 Al alloy after annealing
Author(s) -
Shi-Liang Wu,
Yeqing Chen,
Yunhai Wu,
Shaojie Wang,
Wen Xi-Yu,
Tianrui Zhai
Publication year - 2006
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.55.6129
Subject(s) - materials science , annealing (glass) , positron , doppler broadening , alloy , positron annihilation spectroscopy , positron lifetime spectroscopy , positron annihilation , vacancy defect , dissolution , annihilation radiation , analytical chemistry (journal) , molecular physics , condensed matter physics , atomic physics , metallurgy , spectral line , chemistry , nuclear physics , physics , electron , chromatography , astronomy
Hot band of a continuous cast AA 2037 Al alloy was annealed at different temperatures ranging from room temperature to 500℃ for 3h. Vacancy-solute interaction and precipitates in the hot band samples during annealing were investigated by positron annihilation techniques, coincidence Doppler broadening (CDB) of positron annihilation radiation and positron lifetime spectroscopy, and other methods. The experimental results indicated that there existed V-Cu and V-Cu-Mg complexes at room temperature. At 200℃, positron mean lifetime shows a peak value because of the formation of semicoherent particles. The characteristic shape of Mn was observed in the CDB ratio curve, which indicated the formation of V-Mg-Mn complexes or the existence of Mn clusters in the semicoherent particles. Above 250℃, coarsening and dissolution of semicoherent particles resulted in the decrease of mean lifetime and disappearance of the Mn signal, but the Cu signal increased clearly with annealing temperature. After 350℃, the Cu signal tended to saturation, which reflected that the Cu dissolved might agglomerate and cluster with vacancies during cooling the sample to room temperature, while new increase of mean lifetime might be attributed to the formation of incoherent phase, which was verified by DSC curve.