TY - JOUR
T1 - Positron annihilation study of hot band of a continuous cast AA 2037 Al alloy after annealing
AU - Wu, Shi Liang
AU - Chen, Ye Qing
AU - Wu, Yi Chu
AU - Wang, Shao Jie
AU - Wen, Xi Yu
AU - Zhai, Tong Guang
PY - 2006/11
Y1 - 2006/11
N2 - Hot band of a continuous cast AA 2037 Al alloy was annealed at different temperatures ranging from room temperature to 500°C for 3 h. 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°C, 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°C, 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°C, 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.
AB - Hot band of a continuous cast AA 2037 Al alloy was annealed at different temperatures ranging from room temperature to 500°C for 3 h. 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°C, 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°C, 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°C, 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.
KW - Anneal
KW - Positron annihilation technique
KW - Precipitation
KW - Vacancy-solute complex
UR - http://www.scopus.com/inward/record.url?scp=33846045648&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33846045648&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:33846045648
SN - 1000-3290
VL - 55
SP - 6129
EP - 6135
JO - Wuli Xuebao/Acta Physica Sinica
JF - Wuli Xuebao/Acta Physica Sinica
IS - 11
ER -