JIANG Daming
,
SUN Fenglian
,
HONG Bandc
,
LEI TingquanHarbin Institute of Technology
,
Harbin
,
ChinaDOWNHAM D A
,
LORIMER G WUniversity of Manchester
,
UK
金属学报(英文版)
The variations of microstructure and tensile behavior of an Al-Li-Cu-Mg-Zr alloy during aging are studied in this paper. It has been found that the fine δ-phase precipitated in the underaging condition and that the δ-, S-and T1-phases precipitate in the peak aging and the overaging conditions. The alloy exhibits transgranular fracture on the underaging condition, and mixture of transgranular and intergranular ruptures in the peak aging and overaging conditions.
关键词:
A1 alloy 8090
,
null
,
null
,
null
S.Q.Wang1
,
2) and H.Q.Ye1) 1) Laboratory of Atomic Imaging of Solids
,
Institute of Metal Research
,
The Chinese Academy of Sciences
,
Shenyang 110015
,
China 2)Department of Materials Science and Metallurgy
,
University of Cambridge
,
Cambridge CB2 3QZ
,
UK
金属学报(英文版)
Apeculiar crystal defect was observed by experiment of high resolution electron microscopy( HREM) .It wasidentifiedtoformed bytwothreading dislocationsand asegmentof(11 20) domain boundary. An atomicstructure model was proposed for the anomalous defect. Theresultofthe weak beam experimentofelectron microscopeaffirmedthesuggested model.Thestructuralpropertiesofseveral GaN(11 2 0) domain boundaries werestudied by Molec ular Dynamicscalculations. Thetheoreticalresultsshowedthatthelike atom bonding domain boundary, whichcomposesthe main partofthe peculiar defect, has much higher formationenergy than itcounterpartof unlike atom bonding domain boundary. Theoutcome providesanotherevidenceforthesuggested model.
关键词:
HREM
,
null
,
null
,
null
,
null
