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	Author	Wang, X.; Yao, X.; Schryvers, D.; Verlinden, B.; Wang, G.; Zhao, G.; Van Humbeeck, J.; Kustov, S.
	Title	Anomalous stress-strain behavior of NiTi shape memory alloy close to the border of superelastic window			Type	A1 Journal article
	Year	2021	Publication	Scripta Materialia	Abbreviated Journal	Scripta Mater
	Volume	204	Issue		Pages	114135
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	In this work, we report an anomalous phenomenon on superelastic cycling of NiTi shape memory alloys when deforming at the temperature close to the border of superelastic window. New unexpected effects are found-(i) critical stress for inducing martensite transformation during the second loading cycle is higher than that of the first cycle; ( ii ) the plateau stress of the second cycle decreases to the original level when the strain overcomes the limit of the first cycle; ( iii ) transition from good superelasticity in the first cycle to fully irreversible strain in the second. We propose that defects generated during the first superelastic cycle close to the border of superelastic window impede following stress-induced martensitic transformations, leading to the increase of critical stress beyond yield stress of the B2 matrix, and thus functional fatigue of NiTi alloys. (c) 2021 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000690441400007	Publication Date	2021-07-14
	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		Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.747
	Call Number	UA @ admin @ c:irua:181658			Serial	6853
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	Author	Pourbabak, S.; Verlinden, B.; Van Humbeeck, J.; Schryvers, D.
	Title	DSC cycling effects on phase transformation temperatures of micron and submicron grain Ni_50.8Ti_49.2 microwires			Type	A1 Journal article
	Year	2020	Publication	Shape memory and superelasticity	Abbreviated Journal
	Volume		Issue		Pages	1-10
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The effect of thermal cycling parameters on the phase transformation temperatures of micron and submicron grain size recrystallized Ni-Ti microwires was investigated. The suppression of martensitic transformation by thermal cycling was found to enhance when combined with room temperature aging between the cycles and enhances even more when aged at elevated temperature of 100 degrees C. While aging at room temperature alone has no clear effect on the martensitic transformation, elevated temperature aging at 100 degrees C alone suppresses the martensitic transformation. All aforementioned effects were found to be stronger in large grain samples than in small grain samples. Martensitic transformation suppression in all cases was in line with the formation of Ni4Ti3 precursors in the form of < 111 & rang;(B2) Ni clusters as concluded from the observed diffuse intensity in the electron diffraction patterns revealing short-range ordering enhancement. Performing thermal cycling in some different temperature ranges to separate the effect of martensitic transformation and high temperature range of DSC cycling revealed that both high temperature- and martensitic transformation-included cycles enhance the short-range ordering.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000530232800001	Publication Date	2020-05-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2199-384x; 2199-3858	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	1	Open Access	Not_Open_Access
	Notes	; S.P. would like to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. ;			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:169514			Serial	6492
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	Author	Pourbabak, S.; Montero-Sistiaga, M.L.; Schryvers, D.; Van Humbeeck, J.; Vanmeensel, K.
	Title	Microscopic investigation of as built and hot isostatic pressed Hastelloy X processed by Selective Laser Melting			Type	A1 Journal article
	Year	2019	Publication	Materials characterization	Abbreviated Journal	Mater Charact
	Volume	153	Issue		Pages	366-371
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Microstructural characteristics of Hastelloy X produced by Selective Laser Melting have been investigated by various microscopic techniques in the as built (AB) condition and after hot isostatic pressing (HIP). At sub-grain level the AB material consists of columnar high density dislocation cells while the HIP sample consists of columnar sub-grains with lower dislocation density that originate from the original dislocation cells, contradicting existing models. The sub-grains contain nanoscale precipitates enriched in Al, Ti, Cr and O, located at sub-grain boundaries in the AB condition and within the grains after HIP. At some grain boundaries, micrometer sized chromium carbides are detected after HIP. Micro hardness within the grains was found to decrease after HIP, which was attributed to the decrease in dislocation density due to recovery annealing.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000472696900040	Publication Date	2019-05-21
	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	2	Open Access	Not_Open_Access
	Notes	S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine and financial support. This work was also made possible through the AUHA13009 grant “TopSPIN for TEM nanostatistics” of the Flemish HERCULES foundation.			Approved	Most recent IF: 2.714
	Call Number	EMAT @ emat @UA @ admin @ c:irua:159974			Serial	5178
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	Author	Pourbabak, S.; Orekhov, A.; Samaee, V.; Verlinden, B.; Van Humbeeck, J.; Schryvers, D.
	Title	In-Situ TEM Stress Induced Martensitic Transformation in Ni50.8Ti49.2 Microwires			Type	A1 Journal article
	Year	2019	Publication	Shape memory and superelasticity	Abbreviated Journal	Shap. Mem. Superelasticity
	Volume	5	Issue	2	Pages	154-162
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In-situ transmission electron microscopy tensile straining is used to study the stress induced martensitic transformation in Ni50.8Ti49.2. Two microwire samples with different heat treatment are investigated from which one single crystal and three polycrystalline TEM specimens, the latter with micro- and nano-size grains, have been produced. The measured Young’s modulus for all TEM specimens is around 70 GPa, considerably higher than the averaged 55 GPa of the original microwire sample. The height of the superelastic stress plateau shows an inverse relationship with the specimen thickness for the polycrystalline specimens. Martensite starts nucleating within the elastic region of the stress–strain curve and on the edges of the specimens while also grain boundaries act as nucleation sites in the polycrystalline specimens. When a martensite plate reaches a grain boundary in the polycrystalline specimen, it initiates the transformation in the neighboring grain at the other side of the grain boundary. In later stages martensite plates coalesce at higher loads in the stress plateau. In highly strained specimens, residual martensite remains after release.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000472940200002	Publication Date	2019-05-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2199-384X	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	Saeid Pourbabak likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N. This work was also made possible through the AUHA13009 Grant “TopSPIN for TEM nanostatistics” of the Flemish HERCULES foundation.			Approved	Most recent IF: NA
	Call Number	EMAT @ emat @UA @ admin @ c:irua:159989			Serial	5177
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	Author	Montero-Sistiaga, M.L.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D.; Vanmeensel, K.
	Title	Microstructure and mechanical properties of Hastelloy X produced by HP-SLM (high power selective laser melting)			Type	A1 Journal article
	Year	2019	Publication	Materials & design	Abbreviated Journal	Mater Design
	Volume	165	Issue		Pages	107598
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In order to increase the production rate during selective laser melting (SLM), a high power laser with a large beam diameter is used to build fully dense Hastelloy X parts. Compared to SLM with a low power and small diameter beam, the productivity was increased from 6 mm3/s to 16 mm3/s, i.e. 2.6 times faster. Besides the productivity benefit, the influence of the use of a high power laser on the rapid solidification microstructure and concomitant material properties is highlighted. The current paper compares the microstructure and tensile properties of Hastelloy X built with low and high power lasers. The use of a high power laser results in wider and shallower melt pools inducing an enhanced morphological and crystallographic texture along the building direction (BD). In addition, the increased heat input results in coarser sub-grains or high density dislocation walls for samples processed with a high power laser. Additionally, the influence of hot isostatic pressing (HIP) as a post-processing technique was evaluated. After HIP, the tensile fracture strain increased as compared to the strain in the as-built state and helped in obtaining competitive mechanical properties as compared to conventionally processed Hastelloy X parts.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000458259300020	Publication Date	2019-01-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0264-1275	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.364	Times cited	15	Open Access	OpenAccess
	Notes	This research was supported by the ENGIE Research and Technology Division. The authors acknowledge ENGIE Research and Technology Division for the use of the SLM280HL machine. S.P. likes to thank the Flemish Science Foundation FWO for financial support under Project G.0366.15N.			Approved	Most recent IF: 4.364
	Call Number	EMAT @ emat @UA @ admin @ c:irua:157469			Serial	5176
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	Author	Wang, X.; Kustov, S.; Li, K.; Schryvers, D.; Verlinden, B.; Van Humbeeck, J.
	Title	Effect of nanoprecipitates on the transformation behavior and functional properties of a Ti50.8 at.% Ni alloy with micron-sized grains			Type	A1 Journal article
	Year	2015	Publication	Acta materialia	Abbreviated Journal	Acta Mater
	Volume	82	Issue	82	Pages	224-233
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	In order to take advantage of both grain refinement and precipitation hardening effects, nanoscaled Ni4Ti3 precipitates are introduced in a Ti50.8 at.% Ni alloy with micron-sized grains (average grain size of 1.7 μm). Calorimetry, electrical resistance studies and thermomechanical tests were employed to study the transformation behavior and functional properties in relation to the obtained microstructure. A significant suppression of martensite transformation by the obtained microstructure is observed. The thermomechanical tests show that the advantageous properties of both grain refinement and precipitation hardening are combined in the developed materials, resulting in superior shape memory characteristics and stability of pseudoelasticity. It is concluded that introducing nanoscaled Ni4Ti3 precipitates into small grains is a new approach to improve the functional properties of NiTi shape memory alloys.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000347017800021	Publication Date	2014-10-04
	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	51	Open Access
	Notes	Fwo			Approved	Most recent IF: 5.301; 2015 IF: 4.465
	Call Number	c:irua:120469			Serial	824
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	Author	Wang, X.; Li, K.; Schryvers, D.; Verlinden, B.; Van Humbeeck, J.
	Title	R-phase transition and related mechanical properties controlled by low-temperature aging treatment in a Ti50.8 at.% Ni thin wire			Type	A1 Journal article
	Year	2014	Publication	Scripta materialia	Abbreviated Journal	Scripta Mater
	Volume	72-73	Issue		Pages	21-24
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	A cold-drawn Ti50.8 at.% Ni wire was annealed at 600 °C for 30 min, followed by aging at 250 °C for different times. A microstructure with small grains and nanoscaled precipitates was obtained. The thermally induced martensite transformation is suppressed in the samples aged for 4 h or longer, leaving a one-stage R-phase transition between −150 and +150 °C. The transformation behavior, work output and recovery stress associated with the R-phase transition are presented.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000329148500006	Publication Date	2013-10-17
	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	27	Open Access
	Notes	Fwo			Approved	Most recent IF: 3.747; 2014 IF: 3.224
	Call Number	UA @ lucian @ c:irua:111847			Serial	2806
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	Author	Wang, X.; Amin-Ahmadi, B.; Schryvers, D.; Verlinden, B.; Van Humbeeck, J.
	Title	Effect of annealing on the transformation behavior and mechanical properties of two nanostructured Ti-50.8at.%Ni thin wires produced by different methods			Type	A1 Journal article
	Year	2013	Publication	Materials science forum	Abbreviated Journal
	Volume	738/739	Issue		Pages	306-310
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A Ti-50.8at.%Ni wire produced using a co-drawing method and a commercial Ti-50.8at.%Ni wire were annealed at different temperatures between 450°C and 700°C. Grains with diameter less than 100nm were revealed by transmission electron microscopy for both wires before annealing treatment. However, the microstructural heterogeneity of the co-drawn wire is more obvious than that of the commercial wire. Multi-stage martensitic transformation was observed in the co-drawn wire, compared with the one-stage A↔M transformation in the commercial wire after annealing at 600°C for 30min. The differences of total elongation, plateau strain and pseudoelastic recoverable strain between the commercial wire and the co-drawn wire were also observed. The differences of the transformation behavior and mechanical properties between the commercial wire and the co-drawn wire are attributed to the microstructural difference between these two wires.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lausanne	Editor
	Language		Wos	000316089000055	Publication Date	2013-03-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1662-9752;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	5	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:104691			Serial	798
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	Author	Schryvers, D.; Shi, H.; Martinez, G.T.; Van Aert, S.; Frenzel, J.; Van Humbeeck, J.
	Title	Nano- and microcrystal investigations of precipitates, interfaces and strain fields in Ni-Ti-Nb by various TEM techniques			Type	P1 Proceeding
	Year	2013	Publication	Materials science forum T2 – 9th European Symposium on Martensitic Transformations (ESOMAT 2012), SEP 09-16, 2012, St Petersburg, RUSSIA	Abbreviated Journal
	Volume	738/739	Issue		Pages	65-71
	Keywords	P1 Proceeding; Electron microscopy for materials research (EMAT)
	Abstract	In the present contribution several advanced electron microscopy techniques are employed in order to describe chemical and structural features of the nano- and microstructure of a Ni45.5Ti45.5Nb9 alloy. A line-up of Nb-rich nano-precipitates is found in the Ni-Ti-rich austenite of as-cast material. Concentration changes of the matrix after annealing are correlated with changes in the transformation temperatures. The formation of rows and plates of larger Nb-rich precipitates and particles is described. The interaction of a twinned martensite plate with a Nb-rich nano-precipitate is discussed and the substitution of Nb atoms on the Ti-sublattice in the matrix is confirmed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lausanne	Editor
	Language		Wos	000316089000011	Publication Date	2013-03-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1662-9752;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	2	Open Access
	Notes	Fwo			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:104692			Serial	2247
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	Author	Shi, H.; Pourbabak, S.; Van Humbeeck, J.; Schryvers, D.
	Title	Electron microscopy study of Nb-rich nanoprecipitates in NiTiNb and their influence on the martensitic transformation			Type	A1 Journal article
	Year	2012	Publication	Scripta materialia	Abbreviated Journal	Scripta Mater
	Volume	67	Issue	12	Pages	939-942
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Nb-rich nanoprecipitates in the matrix of an annealed commercial NiTiNb alloy are investigated by scanning and transmission electron microscopy, including slice-and-view and chemical analysis. The precipitates have a diameter of around 100 nm, are faceted and have a cube-on-cube relation with the B2 matrix. In situ TEM cooling shows that the martensitic transformation is hampered by the presence of these precipitates. The latter could explain the increase in hysteresis when compared with the binary system.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000311135000005	Publication Date	2012-08-27
	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	29	Open Access
	Notes	Fwo			Approved	Most recent IF: 3.747; 2012 IF: 2.821
	Call Number	UA @ lucian @ c:irua:101486			Serial	971
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	Author	Tian, H.; Schryvers, D.; Liu, D.; Jiang, Q.; van Humbeeck, J.
	Title	Stability of Ni in nitinol oxide surfaces			Type	A1 Journal article
	Year	2011	Publication	Acta biomaterialia	Abbreviated Journal	Acta Biomater
	Volume	7	Issue	2	Pages	892-899
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The stability of Ni in titanium oxide surface layers on nitinol wires known to release certain amounts of Ni was investigated by first principles density functional theory and transmission electron microscopy. The oxides were identified as a combination of TiO and TiO2 depending on the thickness of the layer. The calculations indicate that free Ni atoms can exist in TiO at ambient temperature while Ni particles form in TiO2, which was confirmed by the transmission electron microscopy observations. The results are discussed with respect to surface stability and Ni release due to free Ni atoms and Ni particles.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	S.l.	Editor
	Language		Wos	000286707700047	Publication Date	2010-09-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1742-7061;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.319	Times cited	39	Open Access
	Notes	Fwo			Approved	Most recent IF: 6.319; 2011 IF: 4.865
	Call Number	UA @ lucian @ c:irua:85998			Serial	3128
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	Author	Delville, R.; Kasinathan, S.; Zhang, Z.; van Humbeeck, J.; James, R.D.; Schryvers, D.
	Title	Transmission electron microscopy study of phase compatibility in low hysteresis shape memory alloys			Type	A1 Journal article
	Year	2010	Publication	Philosophical magazine	Abbreviated Journal	Philos Mag
	Volume	90	Issue	1/4	Pages	177-195
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Recent findings have linked low hysteresis in shape memory alloys with phase compatibility between austenite and martensite. To investigate the evolution of microstructure as phase compatibility increases and hysteresis is reduced, transmission electron microscopy was used to study the alloy system Ti50Ni50xPdx, where the composition is systemically tuned to approach perfect compatibility. Changes in morphology, twinning density and twinning modes are reported, along with special microstructures occurring when compatibility is achieved. In addition, the interface between austenite and a single variant of martensite was studied by high-resolution and conventional electron microscopy. The low energy configuration of the interface detailed in this article suggests that it plays an important role in the lowering of hysteresis compared to classical habit plane interfaces.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000274576500013	Publication Date	2010-01-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1478-6435;1478-6443;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.505	Times cited	70	Open Access
	Notes	Multimat; FWO			Approved	Most recent IF: 1.505; 2010 IF: 1.304
	Call Number	UA @ lucian @ c:irua:79859			Serial	3718
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	Author	Tian, H.; Schryvers, D.; Shabalovskaya, S.; van Humbeeck, J.
	Title	TEM study of the mechanism of Ni ion release from Nitinol wires with original oxides			Type	P1 Proceeding
	Year	2009	Publication		Abbreviated Journal
	Volume		Issue		Pages	05027,1-05027,6
	Keywords	P1 Proceeding; Electron microscopy for materials research (EMAT)
	Abstract	The surface of commercial Nitinol wires with original oxides and a thickness in the 30-190 nm range was investigated by different state of art TEM techniques. The oxide surface layer was identified as a combination of TiO and TiO2 depending on the processing of the wire. Between the core of the wires and the oxidized surface, an interfacial Ni3Ti nanolayer was observed while Ni nanoparticles are found inside the original oxide. The particle sizes, their distribution in the surface and the Ti-O stoichiometry were deduced from the analysis of the obtained data. Molecular dynamics calculations performed for evaluation of the stability of Ni particles relative to the atomic state revealed that a pure Ni particle has a lower energy than free Ni atoms inside the TiO2 lattice. The obtained results are discussed with respect to surface stability and Ni release in the human body.
	Address
	Corporate Author				Thesis
	Publisher	Edp	Place of Publication	Coutaboeuf	Editor
	Language		Wos	000274582300092	Publication Date	2009-08-31
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	1	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:81954			Serial	3493
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	Author	Tian, H.; Schryvers, D.; Mohanchandra, K.P.; Carman, G.P.; van Humbeeck, J.
	Title	Fabrication and characterization of functionally graded Ni-Ti multilayer thin films			Type	A1 Journal article
	Year	2009	Publication	Functional materials letters	Abbreviated Journal	Funct Mater Lett
	Volume	2	Issue	2	Pages	61-66
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A functionally graded multilayer NiTi thin film was deposited on a SiO2/Si substrate by d.c. sputtering using a ramped heated NiTi alloy target. The stand-alone films were crystallized at 500°C in vacuum better than 10-7 Torr. Transmission electron microscopy micrographs taken along the film cross section show two distinct regions, thin and thick, with weak R and B2 phases, respectively. The film compositions along the thickness were measured and quantified using the standard-less EELSMODEL method. The film deposited during the initial thermal ramp (thin regions) displays an average of 54 at.% Ni while the film deposited at a more elevated target temperature (thick regions) shows about 51 at.% Ni.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000271077000003	Publication Date	2009-07-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1793-6047;1793-7213;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.234	Times cited	9	Open Access
	Notes	Fwo			Approved	Most recent IF: 1.234; 2009 IF: 2.561
	Call Number	UA @ lucian @ c:irua:77655			Serial	1165
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	Author	Tian, H.; Schryvers, D.; Shabalovskaya, S.; van Humbeeck, J.
	Title	Microstructure of surface and subsurface layers of a Ni-Ti shape memory microwire			Type	A1 Journal article
	Year	2009	Publication	Microscopy and microanalysis	Abbreviated Journal	Microsc Microanal
	Volume	15	Issue		Pages	62-70
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The microstructure of a 55 Êm diameter, cold-worked Ni-Ti microwire is investigated by different transmission electron microscopy techniques. The surface consists of a few hundred nanometer thick oxide layer composed of TiO and TiO2 with a small fraction of inhomogeneously distributed Ni. The interior of the wire has a core-shell structure with primarily B2 grains in the 1 Êm thick shell, and heavily twinned B19 martensite in the core. This core-shell structure can be explained by a concentration gradient of the alloying elements resulting in a structure separation due to the strong temperature dependence of the martensitic start temperature. Moreover, in between the B2 part of the metallic core-shell and the oxide layer, a Ni3Ti interfacial layer is detected.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge, Mass.	Editor
	Language		Wos	000262912700009	Publication Date	2009-01-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1431-9276;1435-8115;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.891	Times cited	15	Open Access
	Notes	FWO G.0465.05; Multimat			Approved	Most recent IF: 1.891; 2009 IF: 3.035
	Call Number	UA @ lucian @ c:irua:72319			Serial	2074
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	Author	Shabalovskaya, S.A.; Tian, H.; Anderegg, J.W.; Schryvers, D.U.; Carroll, W.U.; van Humbeeck, J.
	Title	The influence of surface oxides on the distribution and release of nickel from Nitinol wires			Type	A1 Journal article
	Year	2009	Publication	Biomaterials	Abbreviated Journal	Biomaterials
	Volume	30	Issue	4	Pages	468-477
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The patterns of Ni release from Nitinol vary depending on the type of material (NiTi alloys with low or no processing versus commercial wires or sheets). A thick TiO2 layer generated on the wire surface during processing is often considered as a reliable barrier against Ni release. The present study of Nitinol wires with surface oxides resulting from production was conducted to identify the sources of Ni release and its distribution in the surface sublayers. The chemistry and topography of the surfaces of Nitinol wires drawn using different techniques were studied with XPS and SEM. The distribution of Ni into surface depth and the surface oxide thickness were evaluated using Auger spectroscopy, TEM with FIB and ELNES. Ni release was estimated using either ICPA or AAS. Potentiodynamic potential polarization of selected wires was performed in as-received state with no strain and in treated strained samples. Wire samples in the as-received state showed low breakdown potentials (200 mV); the improved corrosion resistance of these wires after treatment was not affected by strain. It is shown how processing techniques affect surface topography, chemistry and also Ni release. Nitinol wires with the thickest surface oxide TiO2 (up to 720 nm) showed the highest Ni release, attributed to the presence of particles of essentially pure Ni whose number and size increased while approaching the interface between the surface and the bulk. The biological implications of high and lasting Ni release are also discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Guildford	Editor
	Language		Wos	000262065500006	Publication Date	2008-11-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0142-9612;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.402	Times cited	102	Open Access
	Notes	Fwo; G.0465.05			Approved	Most recent IF: 8.402; 2009 IF: 7.365
	Call Number	UA @ lucian @ c:irua:72320			Serial	1641
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	Author	Srivastava, A.K.; Schryvers, D.; van Humbeeck, J.
	Title	Grain growth and precipitation in an annealed cold-rolled Ni_50.2Ti_49.8 alloy			Type	A1 Journal article
	Year	2007	Publication	Intermetallics	Abbreviated Journal	Intermetallics
	Volume	15	Issue	12	Pages	1538-1547
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Chicago, Ill.	Editor
	Language		Wos	000250930300006	Publication Date	2007-08-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0966-9795;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.14	Times cited	37	Open Access
	Notes	FWO project G.0465.05; EU RTN			Approved	Most recent IF: 3.14; 2007 IF: 2.219
	Call Number	UA @ lucian @ c:irua:65851			Serial	1363
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	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
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	Author	Schryvers, D.; Firstov, G.S.; Seo, J.W.; van Humbeeck, J.; Koval, Y.N.
	Title	Unit cell determination in CuZr martensite by EM and X-ray diffraction			Type	A1 Journal article
	Year	1997	Publication	Scripta materialia	Abbreviated Journal	Scripta Mater
	Volume	36	Issue		Pages	1119-1125
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	A1997WV99600007	Publication Date	0000-00-00
	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	76	Open Access
	Notes				Approved	Most recent IF: 3.747; 1997 IF: 0.645
	Call Number	UA @ lucian @ c:irua:21344			Serial	3811
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	Author	Schryvers, D.; Toth, L.; van Humbeeck, J.; Beyer, J.
	Title	Ni₂Al versus Ni₅Al₃ ordering in Ni₆₅Al₃₅ austenite and martensite			Type	A1 Journal article
	Year	1995	Publication	Journal de physique: colloques, suppléments	Abbreviated Journal
	Volume	5	Issue	8	Pages	1029-1034
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Les Ulis	Editor
	Language		Wos	A1995TX21300082	Publication Date	2014-07-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1155-4339;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	12	Open Access
	Notes				Approved	PHYSICS, APPLIED 47/145 Q2 #
	Call Number	UA @ lucian @ c:irua:13167			Serial	3548
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