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Author | Yang, M.; Orekhov, A.; Hu, Z.-Y.; Feng, M.; Jin, S.; Sha, G.; Li, K.; Samaee, V.; Song, M.; Du, Y.; Van Tendeloo, G.; Schryvers, D. | ||||
Title | Shearing and rotation of β'' and β' precipitates in an Al-Mg-Si alloy under tensile deformation : in-situ and ex-situ studies | Type | A1 Journal article | ||
Year ![]() |
2021 | Publication | Acta Materialia | Abbreviated Journal | Acta Mater |
Volume | 220 | Issue | Pages | 117310 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The interaction between dislocations and nano-precipitates during deformation directly influences hardening response of precipitation-strengthening metals such as Al-Mg-Si alloys. However, how coherent and semi-coherent nano-precipitates accommodate external deformation applied to an Al alloy remains to be elucidated. In-situ tensile experiments in a transmission electron microscope (TEM) were conducted to study the dynamic process of dislocations cutting through coherent needle-like beta '' precipitates with diameters of 3 similar to 8 nm. Comprehensive investigations using in-situ, ex-situ TEM and atom probe tomography uncovered that beta '' precipitates were firstly sheared into small fragments, and then the rotation of the fragments, via sliding along precipitate/matrix interfaces, destroyed their initially coherent interface with the Al matrix. In contrast, semi-coherent beta' precipitates with sizes similar to beta '' were more difficult to be fragmented and accumulation of dislocations at the interface increased interface misfit between beta' and the Al matrix. Consequently, beta' precipitates could basically maintain their needle-like shape after the tensile deformation. This research gains new insights into the interaction between nano-precipitates and dislocations. (C) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000705535300005 | Publication Date | 2021-09-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.301 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 5.301 | |||
Call Number | UA @ admin @ c:irua:182528 | Serial | 6884 | ||
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Author | Yang, M.; Chen, H.; Orekhov, A.; Lu, Q.; Lan, X.; Li, K.; Zhang, S.; Song, M.; Kong, Y.; Schryvers, D.; Du, Y. | ||||
Title | Quantified contribution of β″ and β′ precipitates to the strengthening of an aged Al–Mg–Si alloy | Type | A1 Journal article | ||
Year ![]() |
2020 | Publication | Materials Science And Engineering A-Structural Materials Properties Microstructure And Processing | Abbreviated Journal | Mat Sci Eng A-Struct |
Volume | 774 | Issue | Pages | 138776 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | It is generally believed that β00 precipitates, rather than β0 precipitates, are the major strengthening precipitates in aged Al–Mg–Si alloys. The reason for this difference is not well understood. To clarify this, two samples of the same Al–Mg–Si alloy but with different aging states were prepared. The under-aged sample only contains nanoprecipitates of the β00 type, while the peak-aged one contains nearly equal volumes of β00 and β0 precipitates. We have, for the first time, separated the strengthening effect of the contribution from βʺ and βʹ precipitates, respectively, by an indirect approach based on high-precision measurements of volume fractions, number densities, sizes, proportions of the precipitates, their lattice strains, the composition and grain size of the matrix. The β0 precipitates, which take 45.6% of the total precipitate volume in the peak-aged sample, contribute to the entire precipitation strengthening by only 31.6%. The main reason why they are less useful compared to β00 precipitates has been found to be associated with their smaller lattice strains relative to the matrix, which is 0.99% versus 2.10% (for β00 ). |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000514747200001 | Publication Date | 2019-12-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0921-5093 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.4 | Times cited | Open Access | OpenAccess | |
Notes | National Natural Science Foundation of China, 51531009 51711530713 51501230 ; Central South University, 2018gczd033 ; Flemish Science Foundation, VS.026.18N ; Program for Guangdong Introducing Innovative and Entrepreneurial Teams, 2016ZT06G025 ; Guangdong Natural Science Foundation, 2017B030306014 ; | Approved | Most recent IF: 6.4; 2020 IF: 3.094 | ||
Call Number | EMAT @ emat @c:irua:165290 | Serial | 5440 | ||
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Author | Li, K.; Idrissi, H.; Sha, G.; Song, M.; Lu, J.; Shi, H.; Wang, W.; Ringer, S.P.; Du, Y.; Schryvers, D. | ||||
Title | Quantitative measurement for the microstructural parameters of nano-precipitates in Al-Mg-Si-Cu alloys | Type | A1 Journal article | ||
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2016 | Publication | Materials characterization | Abbreviated Journal | Mater Charact |
Volume | 118 | Issue | 118 | Pages | 352-362 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Size, number density and volume fraction of nano-precipitates are important microstructural parameters controlling the strengthening of materials. In this work a widely accessible, convenient, moderately time efficient method with acceptable accuracy and precision has been provided for measurement of volume fraction of nano-precipitates in crystalline materials. The method is based on the traditional but highly accurate technique of measuring foil thickness via convergent beam electron diffraction. A new equation is proposed and verified with the aid of 3-dimensional atom probe (3DAP) analysis, to compensate for the additional error resulted from the hardly distinguishable contrast of too short incomplete precipitates cut by the foil surface. The method can be performed on a regular foil specimen with a modem LaB6 or field-emission-gun transmission electron microscope. Precisions around +/- 16% have been obtained for precipitate volume fractions of needle-like beta ''/C and Q precipitates in an aged Al-Mg-Si-Cu alloy. The measured number density is dose to that directly obtained using 3DAP analysis by a misfit of 45%, and the estimated precision for number density measurement is about +/- 11%. The limitations of the method are also discussed. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000383292000042 | Publication Date | 2016-06-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1044-5803 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.714 | Times cited | 9 | Open Access | |
Notes | This work is financially supported by National Natural Science Foundation of China (51501230 and 51531009) and Postdoctoral Science Foundation of Central South University (502042057). H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs under Contract No. P7/21 and FWO project G.0576.09N. | Approved | Most recent IF: 2.714 | ||
Call Number | EMAT @ emat @ c:irua:137171 | Serial | 4334 | ||
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Author | Li, K.; Béché, A.; Song, M.; Sha, G.; Lu, X.; Zhang, K.; Du, Y.; Ringer, S.P.; Schryvers, D. | ||||
Title | Atomistic structure of Cu-containing \beta" precipitates in an Al-Mg-Si-Cu alloy | Type | A1 Journal article | ||
Year ![]() |
2014 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
Volume | 75 | Issue | Pages | 86-89 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | The beta '' precipitates in a peak-aged Al-Mg-Si-Cu alloy were measured with an average composition of 28.6Al-38.7Mg-26.5Si-5.17Cu (at.%) using atom probe tomography. High-angle annular dark-field observations revealed that Cu incompletely substitutes for the Mg-1 and Si-3 columns, preferentially for one column in each pair of Si-3. Cu-free Si columns form a parallelogram-shaped network that constitutes the basis of subsequent precipitates in the system, with a = 0.37 nm, b = 0.38 nm, gamma = 113 degrees and c = 0.405 nm. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
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Publisher | Place of Publication | Oxford | Editor | ||
Language | Wos | 000331025200022 | Publication Date | 2013-12-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-6462; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.747 | Times cited | 22 | Open Access | |
Notes | Approved | Most recent IF: 3.747; 2014 IF: 3.224 | |||
Call Number | UA @ lucian @ c:irua:115749 | Serial | 201 | ||
Permanent link to this record |