NANOlab Center of Excellence literature database -- Query Results

	NANOlab Center of Excellence literature database Home \| Show All \| Simple Search \| Advanced Search	Login Quick Search: Field: contains: ...
	31–39 of 39 records found matching your query (RSS \| history):

Select All Deselect All

<< 1 2 >>

List View

Citations

Details

	Records
	Author	Cao, S.; Nishida, M.; Schryvers, D.
	Title	Quantitative three-dimensional analysis of Ni₄Ti₃ precipitate morphology and distribution in polycrystalline Ni-Ti			Type	A1 Journal article
	Year	2011	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	59	Issue	4	Pages	1780-1789
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The three-dimensional size, morphology and distribution of Ni4Ti3 precipitates in a Ni50.8Ti49.2 polycrystalline shape memory alloy with a heterogeneous microstructure have been investigated using a focused ion beam/scanning electron microscopy slice-and-view procedure. The mean volume, central plane diameter, thickness, aspect ratio and sphericity of the precipitates in the grain interior as well as near to the grain boundary were measured and/or calculated. The morphology of the precipitates was quantified by determining the equivalent ellipsoids with the same moments of inertia and classified according to the Zingg scheme. Also, the pair distribution functions describing the three-dimensional distributions were obtained from the coordinates of the precipitate mass centres. Based on this new data it is suggested that the existence of the heterogeneous microstructure could be due to a very small concentration gradient in the grains of the homogenized material and that the resulting multistage martensitic transformation originates in strain effects related to the size of the precipitates and scale differences of the available B2 matrix in between the precipitates.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000287265100045	Publication Date	2010-12-20
	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	34	Open Access
	Notes	Fwo			Approved	Most recent IF: 5.301; 2011 IF: 3.755
	Call Number	UA @ lucian @ c:irua:85533			Serial	2766
Permanent link to this record



	Author	Malard, B.; Pilch, J.; Sittner, P.; Delville, R.; Curfs, C.
	Title	In situ investigation of the fast microstructure evolution during electropulse treatment of cold drawn NiTi wires			Type	A1 Journal article
	Year	2011	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	59	Issue	4	Pages	1542-1556
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Microstructural changes taking place during the heat treatment of cold-worked NiTi alloy are of key interest in shape memory alloy technology, since they are responsible for setting the austenite shape and functional properties of the heat-treated alloy. In this work, microstructural evolution during non-conventional electropulse heat treatment of thin NiTi filaments was investigated in a unique high-speed in situ synchrotron X-ray diffraction experiment with simultaneous evaluation of the tensile force and electrical resistivity of the treated wire. The in situ results provide direct experimental evidence on the evolution of the internal stress and density of defects during fast heating from 20 °C to ∼700 °C. This evidence is used to characterize a sequence of dynamic recovery and recrystallization processes responsible for the microstructure and superelastic functional property changes during the electropulse treatments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000287265100023	Publication Date	2010-12-11
	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	48	Open Access
	Notes				Approved	Most recent IF: 5.301; 2011 IF: 3.755
	Call Number	UA @ lucian @ c:irua:98372			Serial	1583
Permanent link to this record



	Author	Delville, R.; Malard, B.; Pilch, J.; Schryvers, D.
	Title	Microstructure changes during non-conventional heat treatment of thin NiTi wires by pulsed electric current studied by transmission electron microscopy			Type	A1 Journal article
	Year	2010	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	58	Issue	13	Pages	4503-4515
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Transmission electron microscopy, electrical resistivity measurements and mechanical testing were employed to investigate the evolution of microstructure and functional superelastic properties of 0.1 mm diameter as-drawn NiTi wires subjected to a non-conventional heat treatment by controlled electric pulse currents. This method enables a better control of the recovery and recrystallization processes taking place during the heat treatment and accordingly a better control on the final microstructure. Using a stepwise approach of millisecond pulse annealing, it is shown how the microstructure evolves from a severely deformed state with no functional properties to an optimal nanograined microstructure (2050 nm) that is partially recovered through polygonization and partially recrystallized and that has the best functional properties. Such a microstructure is highly resistant against dislocation slip upon cycling, while microstructures annealed for longer times and showing mostly recrystallized grains were prone to dislocation slip, particularly as the grain size exceeds 200 nm.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000279787100020	Publication Date	2010-06-02
	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	110	Open Access
	Notes	Multimat; FWO IAA			Approved	Most recent IF: 5.301; 2010 IF: 3.791
	Call Number	UA @ lucian @ c:irua:83279			Serial	2062
Permanent link to this record



	Author	Idrissi, H.; Renard, K.; Ryelandt, L.; Schryvers, D.; Jacques, P.J.
	Title	On the mechanism of twin formation in FeMnC TWIP steels			Type	A1 Journal article
	Year	2010	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	58	Issue	7	Pages	2464-2476
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Although it is well known that FeMnC TWIP steels exhibit high work-hardening rates, the elementary twinning mechanisms controlling the plastic deformation of these steels have still not been characterized. The aim of the present study is to analyse the extended defects related to the twinning occurrence using transmission electron microscopy. Based on these observations, the very early stage of twin nucleation can be attributed to the pole mechanism with deviation proposed by Cohen and Weertman or to the model of Miura, Takamura and Narita, while the twin growth is controlled by the pole mechanism proposed by Venables. High densities of sessile Frank dislocations are observed within the twins at the early stage of deformation, which can affect the growth and the stability of the twins, but also the strength of these twins and their interactions with the gliding dislocations present in the matrix. This experimental evidence is discussed and compared to recent results in order to relate the defects analysis to the macroscopic behaviour of this category of material.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000276523200018	Publication Date	2010-01-25
	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	244	Open Access
	Notes	Iap			Approved	Most recent IF: 5.301; 2010 IF: 3.791
	Call Number	UA @ lucian @ c:irua:82270			Serial	2441
Permanent link to this record



	Author	Bartova, B.; Wiese, N.; Schryvers, D.; Chapman, J.N.; Ignacova, S.
	Title	Microstructure of precipitates and magnetic domain structure in an annealed Co₃₈Ni₃₃Al₂₉ shape memory alloy			Type	A1 Journal article
	Year	2008	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	56	Issue	16	Pages	4470-4476
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The microstructure of a Co38Ni33Al29 ferromagnetic shape memory alloy was determined by conventional transmission electron microscopy (TEM), electron diffraction studies together with advanced microscopy techniques and in situ Lorentz microscopy. Rod-like precipitates, 1060 nm long, of hexagonal close-packed -Co were confirmed to be present by high-resolution TEM. The orientation relationship between the precipitates and B2 matrix is described by the Burgers orientation relationship. The crystal structure of the martensite obtained after cooling is tetragonal L10 with a (111) twinning plane. The magnetic domain structure was determined during an in situ cooling experiment using the Fresnel mode of Lorentz microscopy. While transformation proceeds from B2 austenite to L10 martensite, new domains are nucleated, leading to a decrease in domain width, with the magnetization lying predominantly along a single direction. It was possible to completely describe the relationship between magnetic domains and crystallographic directions in the austenite phase though complications existed for the martensite phase.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000259931300033	Publication Date	2008-06-11
	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	23	Open Access
	Notes	Multimat			Approved	Most recent IF: 5.301; 2008 IF: 3.729
	Call Number	UA @ lucian @ c:irua:72321			Serial	2072
Permanent link to this record



	Author	Yang, Z.; Tirry, W.; Lamoen, D.; Kulkova, S.; Schryvers, D.
	Title	Electron energy-loss spectroscopy and first-principles calculation studies on a Ni-Ti shape memory alloy			Type	A1 Journal article
	Year	2008	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	56	Issue	3	Pages	395-404
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000253020900011	Publication Date	2007-12-01
	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	20	Open Access
	Notes	Goa; Ec Rtn; Fwo			Approved	Most recent IF: 5.301; 2008 IF: 3.729
	Call Number	UA @ lucian @ c:irua:67462			Serial	931
Permanent link to this record



	Author	Rotaru, G.-M.; Tirry, W.; Sittner, P.; van Humbeeck, J.; Schryvers, D.
	Title	Microstructural study of equiatomic PtTi martensite and the discovery of a new long-period structure			Type	A1 Journal article
	Year	2007	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	55	Issue	13	Pages	4447-4454
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000248436400021	Publication Date	2007-06-04
	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	7	Open Access
	Notes	Fwo G.0465.05; Multimat			Approved	Most recent IF: 5.301; 2007 IF: 3.624
	Call Number	UA @ lucian @ c:irua:65849			Serial	2047
Permanent link to this record



	Author	Viart, N.; Sayed Hassan, R.; Ulhaq-Bouillet, C.; Meny, C.; Panissod, P.; Loison, J.L.; Versini, G.; Huber, F.; Pourroy, G.; Verbeeck, J.; Van Tendeloo, G.
	Title	Oxidation processes at the metal/oxide interface in CoFe₂/CoFe₂O₄ bilayers deposited by pulsed laser deposition			Type	A1 Journal article
	Year	2006	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	54	Issue	1	Pages	191-196
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	CoFe2/CoFe2O4 bilayers were made by pulsed laser ablation of a CoFe2 target on Si(I 0 0) substrates. The metallic layer was deposited first, in vacuum. The oxide was then deposited in an oxidizing O-2:N-2 (20:80) atmosphere. Two different procedures were used for the introduction of the oxidizing atmosphere in the deposition chamber: the laser ablation of the target was either stopped (discontinuous deposition process) or maintained (continuous deposition process) during the 20 min necessary for the establishment of the desired O-2:N-2 pressure. In both cases, the different electronegativities of Fe and Co cause an important modification of the Fe/Co ratio at the metal/oxide interface, with a depletion of Fe in the metal region and of Co in the oxide region. In the continuous procedure, the combination of the kinetic energy given by the ablation process to the Fe and Co adatoms with the one they get from their different affinity towards oxidation allows the formation of a low roughness metal/oxide interface with a high (111) preferred orientation of the CoFe2O4 layer, an induced re-crystallisation of the metal layer underneath and an unusual antiferromagnetic metal/oxide magnetic coupling. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000233784500021	Publication Date	2005-10-15
	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	5	Open Access
	Notes				Approved	Most recent IF: 5.301; 2006 IF: 3.549
	Call Number	UA @ lucian @ c:irua:56043UA @ admin @ c:irua:56043			Serial	2540
Permanent link to this record



	Author	Tirry, W.; Schryvers, D.
	Title	Quantitative determination of strain fields around Ni₄Ti₃ precipitates in NiTi			Type	A1 Journal article
	Year	2005	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	53	Issue	4	Pages	1041-1049
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000226774500014	Publication Date	2004-12-14
	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	97	Open Access
	Notes				Approved	Most recent IF: 5.301; 2005 IF: 3.430
	Call Number	UA @ lucian @ c:irua:55686			Serial	2750
Permanent link to this record