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Materials Science and Engineering A 528 (2011) 59275934

Contents lists available at ScienceDirect

Materials Science and Engineering A

j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / m s e a

Texture and mechanical properties of EUROFER 97 steel processed by ECAP

M. Eddahbi a,, M.A. Monge a, T. Leguey a, P. Fernndez b, R. Pareja a

a Departamento de Fsica, Universidad Carlos III, 28911 Legans, Madrid, Spainb CIEMAT. Avda. Complutense 22. 28040 Madrid, Spain

a r t i c l e i n f o

Article history:

Received 30 November 2010

Received in revised form 4 April 2011

Accepted 5 April 2011Available online 12 April 2011

Keywords:

RAFM steels

EUROFER 97

ECAP processing

Texture

Microtexture

Mechanical properties

a b s t r a c t

The EUROFER 97 steel was processed by equal channel angular pressing (ECAP) at 550 C for four passes

viarouteC. Thestarting material consistedof ferritemartensite dual phase composed by small subgrains

of about 0.5m and low angle boundaries less than 5

. The volume fraction of second phase particleswas around 10 vol.%, besides a texture formed by several fibers orientations belonging to the zone axes

1 1 0, 1 1 1 and 1 1 2. Increasing ECAP deformation, this microstructure became into equiaxed grain

structures of less than 1m, and the misorientation between contiguous grains increased. This refine-

ment of the microstructure was accompanied by the development of a newtexture described by a family

of fiber orientations related by rotations around axes 1 1 0 and 1 1 1. Tensile tests have revealed that

an ECAP treatment at 550 C for two passes could significantly strengthen the tempered material still

maintaining good ductility.

2011 Elsevier B.V. All rights reserved.

1. Introduction

Due to its mechanical properties, long-term stability

and predictability up to 650 C, the reduced activation

ferriticmartensitic EUROFER 97 steel is being considered for

structural applications in the breeding blankets of ITER, and

for the demonstration fusion reactor DEMO [1,2]. The strength

of this steel can be enhanced by precipitation hardening, and

strengthening induced by dislocations, particle dispersion or grain

boundaries. However, precipitation hardening and strengthening

by dislocations or particles dispersion can reduce dramatically

ductility and toughness compared with grain refinement [3].

Ultrafine grained structures can be developed in metals by

severe plastic deformation techniques (SPD), among which ECAP is

a successful method to develop submicron microstructures in bulk

steel [49]. The aim of the present work has been to explore the

capability of warm ECAP fordevelopinga stablegrainstructure and

texture in tempered EUROFER 97 that can enhance its mechanicalbehavior in its operational temperature range, i.e. below 600 C.

2. Experimental procedure

The material used for this study was produced by Bhler

(Austria) with composition (wt.%): 0.11%C, 8.7%Cr, 1%W, 0.1%Ta,

0.19%V, 0.44%Mn, 0.004%S, with the balance Fe (EUROFER 97). The

Corresponding author. Tel.: +34 91 624 8734; fax: +34 91 624 8749.

E-mail address: [email protected] (M. Eddahbi).

as-received plates were normalized at 980 C for 27 min followed

by temperingat 760C for 90min.12mm12mm65mm billets

of the as-tempered material were ECAP processed at 550 C with a

velocity of 10mm min1 through a diewithan intersection angleof

105. The billets were subjected to one, two and four ECAP passes.

They were rotated 180 around its longitudinal axis before insert-

ing in the die for the subsequent ECAP pass, what is referred to as

route C.

Samples for microstructural studies and tensile tests were

machined from the billets, polished with alumina and etched by

solution of 5g FeCl3 +6ml HCl+100ml H2O. The microstructure

was characterized by optical microscopy (OM), Scanning electron

microscopy (SEM) and transmission electron microscopy (TEM).

Room temperature tensile tests were performed on flat tensile

specimens at a constant crosshead rate of 0.04 mm min1 (initial

strain rate of about 3.3105 s1). The specimens with a gauge

length of 20 mm, a width of 3 mm, and a thickness of 1 mm were

cut parallel to the flow plane of the billets as shown in Fig. 1.Texture measurements were accomplished by measurement

of pole figures using the Schulz reflection method, in a Siemens

diffractometer equipped with a D5000 goniometer. The mea-

surements were performed through the range of azimuthal

angles between 0 and 75 in the step mode with incre-ments of== 5. A textureless standard sample of annealedpure iron was used for defocusing correction. Quantitative

three-dimensional orientation distribution functions (ODFs) were

obtained using a Siemens software [10]. These were represented by

iso-intensity lines in equidistant sections, 1 = 10, through the

Euler space defined by 1, and 2 angles. For the representation

0921-5093/$ see front matter 2011 Elsevier B.V. All rights reserved.

doi:10.1016/j.msea.2011.04.006

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5928 M. Eddahbi et al. / Materials Science and Engineering A 528 (2011) 59275934

PD

TD

ND

Die

Die

105

(a)

(b)

Fig. 1. Sketches of (a) the ECAP die used, and (b) samples machined from the ECAP

processed billets for tensile tests.

of the ODFs, a monoclinic symmetry was used resulting in a good

concordance between the measured ODFs and the calculated ones

for all ECAP deformed samples.

Grain orientation maps of the material in the as-tempered

condition and after ECAP deformation were obtained from the

corresponding electron backscattering diffraction (EBSD) patterns

recorded using a HKL Nordlys EBSD system interfaced with a field

emission gun scanning electron microscope FEG-SEM JEOL JSM-

6500F equipped with an energy dispersive spectrometer (EDS).

The applied accelerating voltage and the working distance were

25kV and1520mm, respectively. The EBSD scans using step sizes

of 0.140.18m were performed on 54m43m areas in cen-

tral region of the specimen surfaces parallel to the flow plane.

These surfaces were carefully polished. The EBSD data were ana-

lyzed using the in-house software package CHANNEL 5. The OIM

images applying the usual coloring scheme for the Euler angles

were obtained using the external software package MTEX MatLab

Toolbars for quantitative texture analysis [11]. Grain boundaries

with misorientation between the contiguous grains of mis 10

have been defined as low angle grain boundaries (LABs), or sub-

grain boundaries, and the ones with mis

> 10 referred to as high

angle grain boundaries (HABs).

3. Results and discussion

3.1. Microstructure

Fig. 2 shows the effect of the ECAP processing on the EUROFER

97. The microstructure of thematerialin the as-tempered condition

exhibits laths substructure as Fig. 2(a) and (b) reveal. Both the OM

observations and the SEM analyses revealed that this microstruc-

ture contains small carbide particles as Fig. 2(b) shows. Most of

these particles were found at the prior-austenite boundaries and

along the lath sub-boundaries. Two types of carbides were iden-

tified: Cr-rich M23C6 with sizes of less than 0.2m, and fine

Ta- and V-rich MX carbides. The volume fraction of second phase

particles was estimated of about 10% using SME and EBSD mea-

surements.

Fig. 2. OM and SEM micrographs of EUROFER 97. (a) and (b) microstructures in the as-tempered condition showing martensite laths, carbide particles and prior-austenite

boundaries decorated with carbide particles. Microstructure after (c) and (d) one pass ECAP deformation, and (e) and (f) four ECAP passes. The pressing direction (PD) is

horizontal.

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M. Eddahbi et al. / Materials Science and Engineering A 528 (2011) 59275934 5929

Fig. 3. ECAP deformation effect on the grain structure of the EUROFER 97. (a) and (d) OIM images for as-tempered material and ECAP deformed for four passes, respectively.

(b) and (e) grain size distribution, and (c) and (f) misorientation distribution for the material in the as-tempered condition and ECAP deformed for four passes, respectively.

After the first ECAP pass the microstructure was reoriented

and shear strained as shown in Fig. 2(c) and (d) [12]. After

four passes, Fig. 2(e) and (f), the microstructure turned out

near equiaxed. In addition, the SEM images show that ECAP

deformation did not induce agglomeration of second phase par-

ticles.

3.2. EBSD observations

Fig.3 shows the effectof four ECAP passeson the grain structure.

The indexation of the EBSD patterns also showed that the sam-

ples exhibit a dual phase ferritemartensite microstructure. The

OIM images and the distributions of grain sizes and misorienta-

tion reveal that ECAP deformation under the present conditions

induces grain refinement and misorientation increment in the fer-

rite phase. Moreover, ECAP deformation transformed martensite

into ferrite. The martensite fraction of27 vol.% for the EUROFER

97 in the as-tempered condition was lowered to 5 vol.% after four

ECAP passes.

The as-tempered state consisted of fine subgrains confined in

coarse grains of up to 7m in size as shown in Fig. 3(a) and (b).

Most of the subgrains are of about 0.5m in size. The misorien-

tation histograms corresponding to both ferrite and martensite

phase in as-tempered state revealed the presence of high den-

sity of LABs of less than 5 and low density of HABs as shown

in Fig. 3(c). After four ECAP passes the subgrain size is less

than 1m and the misorientation angle in the ferrite phase

increases, Fig. 3(f).

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Fig. 4. TEM micrographs showing the effect of the ECAP deformation on the microstructure of as-tempered EUROFER 97. (a) Elongated substructure and (b) details showing

the nucleation of subgrains at a grain triple junction for the material ECAP deformed for one pass; the arrows indicate sub-boundaries or dislocation walls. Microstructure

in a sample processed for two passes showing: (c) lamellar and (d) equiaxed grain structure. (e) and (f) images showing equiaxed grains with high density of dislocations in

a sample ECAP deformed for four passes.

3.3. TEM observations

Also, the TEM images shown in Fig. 4 illustrate the ECAP effect

on the microstructure of the EUROFER 97. After the first and sec-

ond pass, the microstructure turned out highly elongated and

shear strained as shown in Fig. 4(a) and (c). The microstructure

after a single pass exhibited a low dislocation density and small

subgrains, or grain domains, as Fig. 4(a) and (b) reveal. These

domains appear to form by the development of a structure of

dislocations walls (indicated by arrows) that can transform into

sub-boundariesand boundaries during further deformation via dis-

location motion and accumulation into the sub-boundaries, i.e. by

extended recovery, also called continuous recrystallization [13].

The sub-boundaries are pinned by small carbide particles retain-

ing the microstructure on the succeeding passes. EBSD analysis

and TEM observations indicate that the mechanism of continuousrecrystallization appears to be the main responsible for the grain

refinement induced by ECAP in EUROFER 97. Nevertheless, the for-

mation of new subgrains is also observed to occur at precipitate

particles associated to sub-boundaries or grain triple junctions as

shown in Fig. 4(b). In particular, the size of the subgrains nucle-

ated at the triple junctions appear to be less than 100 nm, i.e. much

smallerthanthesubgrainsproducedbythemechanismofextended

recovery. Due to the considerable volume fraction of precipitate

particles present in this steel, the mechanism of subgrain nucle-

ation at particles associated to sub-boundaries, or triple junctions,

could significantly contribute to the development of a homoge-

neousultrafine-grained structure.It should be emphasized thatthe

mechanism of subgrain formation apparently induced by particles

associated to sub-boundaries should be different from the particle

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Fig. 5. The ODFs for EUROFER 97, represented through 1-sections (1 = 10) and the spatial arrangement of the fibers in the Euler space, showing the effect of ECAP

deformation. a) and b) as-tempered material; c) and d) after a single pass; e) and f) after two passes and g) and h) after four passes.

stimulated nucleation (PSN) mechanism based on the deformation

zones around the second phase particle [14,15]. This mechanism is

characteristic of some alloys containing hard particles and requires

a critical particle size of12m, below which a subgrain cannot

develop and become into a recrystallization nucleus [14]. Instead,

it is suggestedthatECAP deformationin EUROFER 97 contributes to

activate new slip systems and creates a homogenous distribution

of strain in the surrounding region of a small carbide particle that

favors the dislocation rearrangementinto walland sub-boundaries,

i.e. giving rise to subgrains.

After two ECAP passes the samples exhibited a microstructure

composed of elongated grains containing equiaxed substructure

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Fig. 6. Orientation density functions, f(g), for ECAP deformed EUROFER 97 as a function of1: a) one pass, b) two passes and c) four passes.

as shown in Fig. 4(c) and (d). The corresponding OIM images

obtained from a sample area of 2322m2

reveal enhancement ofthe microstructure fragmentation and a shift of the misorienta-

tion distribution toward high mis values although the LABs arestill themajorfractionof boundaries present in the ECAP deformed

samples. Onthe contrary, theequiaxedsubstructure hada high dis-

location density, and boundaries that exhibited a thick and blunt

image. Afterfour passes, the elongatedstructure is no longer visible

andthemicrostructureisroughlyequiaxedasshownin Fig.4(e)and

(f). This result is in contrast to that obtained for an IF steel, where

the lamellar structure is still retained after four passes via route C

[16].

The morphology of the substructure developed by ECAP will

depend on the initial grain orientation respects to the shear plane

imposed in the ECAP die. This substructure would control the

rearrangement of dislocations into dislocation walls contribut-ing to increase the angular misorientation across the cell walls

or sub-boundaries. The as-tempered material consists of laths

substructure randomly distributed in different orientations into

the volume material (Fig. 2(a) and Fig. 3(a)), which would imply

different ECAP induced substructures depending on their initial

orientation respect the shear plane. ECAP deformation activates

dislocation gliding on the slip planes giving rise to an elongated

lamellar substructure on these planes. After an ECAP pass, this

elongated substructure tends to align almost parallel to the shear

plane, thus should conserve the initial lamellar substructure on

ECAP deformation, although they become more elongated and its

spacing might be reduced.On thecontrary, if thelamellarsubstruc-

ture, or the active slip planes, forms a high angle with shear plane,

a new substructure would be developed, so that ECAP deforma-

tion refines the substructure of these grains. After several ECAP

passes, the lamellar structure would be fragmented resulting in

a more equiaxed and refined substructure with higher misorien-

tation mis across the subgrain boundaries as Fig. 3(f) shows. Theeffectiveness of the ECAP treatment for refining the grain struc-

ture will depend on the change of strain path induced by the ECAP

routes.

3.4. Texture

Fig. 5 shows the effect of ECAP deformation via route C on the

texture of EUROFER 97 material. The ODFs are represented in the

Euler space through 1-sections from 1 = 0180, for the mate-

rial in the as-tempered condition(Fig.5(a)), and ECAP processedfor

onepass(Fig. 5(c)), two passes(Fig.5(e))and four passesvia route C

(Fig. 5(g)). The corresponding spatial arrangements of the ODFs arerepresented in Fig.5(b), (d), (f)and (h) showing the positionsof the

fibersintheEulerspace.Formoredetails,Fig. 6 plotsthe orientation

intensity, f(g), as a function of1 for the ECAP deformed materials.In the present work, the Miller index {h k l}u vw represents an

orientation that has an {h k l} parallel to the flow plane of the bil-

let, i.e. plan normal to ND in Fig. 1, and an u vw direction parallel

to the longitudinal axis of the billet, i.e. PD in Fig. 1. As observed in

Fig.5(a) and (b), the as-tempered material exhibits numerous weak

fibers. This texture results from a combination of severe rolling and

cross rolling underwent by the material before being tempered.

Each fiber is an ensemble of orientations related to each other by

rotationsaround the 1 1 0, 1 1 1 and 1 1 2 axes. Itis worthnotic-

ing that these axes are either parallel to the ND or located at an

azimuth angle.After the first ECAP pass some weak fibers disappear and new

ones form, compare Fig. 5(b) and (d). However, the stronger fiber

components observed in the material ECAP deformed for a single

pass, marked as S1, S2, S3, S4, S5 and S6, remain after four ECAP

passes, although their intensity varies along the skeleton line as

shown in Fig. 6(a)(c). The maximum intensities for these fibers

correspond to {1 1 0}1 2 2, {1 1 0}1 1 1 and {1 1 1}1 2 3 orienta-

tions. The weak fibers, labeled W1, W2 and W3 can be described

by (106)[0 10], (013)[4 31] and (103)[3 8 1] orientations. The

present ECAP induced texture in the steel EUROFER 97 contrast

with the fiber texture 1 1 1 and 1 0 0 and the fibers {1 1 0}u vw

and {h k l}1 1 1 reported for low carbon and interstitial-free

(IF) steels ECAP deformed at room temperature [9,16]. The dis-

crepancies could be attributed to the differences in the ECAP

parameters as well as to the high content of carbide particles in

EUROFER 97.

The crystallographic texture developed during the first ECAP

pass is retained after the succeeding passes as shown in Fig. 5(c)

and (g), albeit the distribution of orientations along the fibers

changes. After the secondECAPpass theintensity of themain fibers

decreases andthe weak fibers vanishor even disappearas occurred

for the W1, W2 and W3-fibers, compare Fig. 6(a) and (b). Then, the

second pass does not reverse the first pass texture to the original

one of the billet as the approach assuming simple shear deforma-

tion at the intersection plane of the die channels predicts for ECAP

processing of bcc materials [17,18]. After the fourth ECAP pass,

the intensities of two main fibers increase respect to the second

pass, and the weak fibers, which are removed or reduced by the

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second pass, reappear. These results indicate that shear deforma-

tion induced by the first pass, or by an odd-numbered pass, is not

reversedby the subsequent pass tothe strainstate ofthe billetat the

beginning or after a previous even-numbered route C pass. In fact,

it hasbeen reported forIF steel that the real ECAP processing condi-

tions alter the cyclic changes of thetexture predictedby the simple

shear model [16,19]. The inhomogeneous strain across the ECAP

processed billet, the complex microstructure, the die geometry and

the interaction with neighboring grains appear to constraint the

capability of a route C pass to reverse shear deformation induced

by thepreviousECAP pass. However, thecyclic tendency of thetex-

ture for going back to the initial one can be still maintained for an

IF steel, in particular if the die angle is changed from 90 to 120

[17,18]. In the present work, the cyclic reversion of the texture by

ECAP via route C neither appears to be partially accomplished even

though a die with =105 is used. The results obtained for tem-pered EUROFER 97 ECAP processed under the present conditions

reveal that shear deformation induced by a pass is practically irre-

versible against a subsequent route C pass. This irreversibility that

is much stronger than the reported for IF steel in Refs. [17,18] may

be attributed to the complex substructure and high concentration

of carbide particles present in the tempered EUROFER 97 steel.

Furthermore, the present texture analyses give rise to issues

related to deformation mechanism responsible for the evolution ofthe microstructure during severe plastic deformation of EUROFER

97. Actually, it was found that the orientations developed during a

single ECAP pass are connected by rotations in the range 1040

around the same axes found for the material in the as-tempered

condition, i.e. around 1 1 0 and 1 1 1 axes. Nevertheless, these

axes are now located between the PD and TD directions. Similar

results are found in the material deformed for two and four ECAP

passes. To illustrate these rotations qualitatively, Fig. 7 shows the

localizationof ND of theorientationsin the cubic stereographicpro-

jection. The differences in the ND distribution withincreasing ECAP

deformation, and keeping the rotation axes 1 1 0 and 1 1 1, are

clearly evident.For one ECAPpass, theS5-fiber orientationsare con-

nected through35 rotationaround[1 1 1] andthose corresponding

to the S6-fiber through rotation of 20 and 10 around [0 1 1] and[1 0 1]. However, both fibers are closely joined together into rota-

tions around 1 1 0 axes after two passes.Furthermore, the S1-fiber

described by a rotation of30 around [1 0 1] transforms into the

s11 and s12-fibers as shown in Fig. 7(a) and (b). The s11-fiber main-

tains the rotation axis [1 0 1] whereas the rotation axis in s12-fiber

is parallel to the ED. These results indicate that route C can pro-

duce significant changes on the distribution of orientations along

the main fibers during ECAP deformation of EUROFER 97.

3.5. Tensile properties

Tensile test true stresstrue strain curves are depicted in Fig. 8.

Thetensilestrengthof thesamplesECAP deformed forone pass and

twopasses viaroute C increasednoticeably in comparison withthatfor the as-tempered material. The yield stress y, ultimate tensile

strength (UTS) and the uniform elongation (u) forthe as-temperedmaterial are 549 MPa, 685 MPa and 9.4%, respectively. After two

passes u decreased to about 7.5% whilst y and UTS increased to

638MPa and 800 MPa, respectively. However, ECAP deformation

for four passes resulted in a decrease in the mechanical properties

compared to two passes (y = 602 MPa, UTS = 746 MPa and u = 4%).It has been reported that route C beyond two passes is inef-

fective for reducing the grain size in an IF steel ECAP processed

at room temperature [17]. The strength decrease in EUROFER 97

deformed for four passes under the present ECAP conditions can-

not be attributed to a limited capability for the grain refinement

beyond the second pass via route C because grain refinement

was still achieved during the fourth pass as the TEM observa-

Fig. 7. Traces of the ND to the fiber orientations in the stereographic projection for

EUROFER 97 ECAP deformed via route C for: a) a single pass, b) two passes and c)

four passes. Each fiber is marked by its corresponding symbol.

tions showed. Even assuming stabilization in the grain refinement

beyond two ECAP passes, this cannot give account for the decrease

in strength and ductility by itself. Nevertheless, the heterogeneous

substructures developed in elongated and equiaxed subgrains

could influence the mechanical behavior of the material. In fact,

the microstructure after two passes is a combination of lamellar

and equiaxed substructures, which evolved into an equiaxed sub-

structure after four passes. Both substructures contribute to strain

hardening at room temperature for a given strain rate, although

hardeningshould be higher in the regions with equiaxed substruc-

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5934 M. Eddahbi et al. / Materials Science and Engineering A 528 (2011) 59275934

0

200

400

600

800

1000

0.150.10.050

As-tempered

One pass ECAP

Two passes ECAP

Four passes ECAP

Truestress,M

Pa

True strain

RT - 3x10-5

s-1

Fig. 8. Effect of ECAP deformation via route C on the tensile properties of as-

tempered EUROFER 97.

tures.Then,the expected flowstress increase in these zones should

be relieved by assumingpropagationof deformation intothe lamel-

lar substructure preventing the localization of high stresses in the

equiaxed substructures. This stress release mechanism could be

responsible for the improvement of tensile properties in the mate-

rial ECAP deformed for one or two passes. So, it appears that the

mechanical behaviorof the ECAPdeformedsteel EUROFER 97 could

be explained in terms of a combination of lamellar and equiaxed

substructures where the morphology, refinement, fraction and ori-

entationof the lamellar substructure would determine the strength

and ductility. Further assessment is needed for a comprehensi-

ble understanding of the strengthening mechanisms competing in

EUROFER 97 taking into account dislocation density, volume frac-

tion of martensite phase and carbide particles.

Also, in the material ECAP deformed for two passes it should

be noted that the 1 1 0 directions are found at 3040 from the

ED of the billet in the S5 and S6-fibers and at 30 in the s11-fiber.

This means that many more subgrains in this case are favorably

oriented to be plastically deformed in comparison with the mate-

rials deformed for one or four ECAP passes, which accounts for the

better tensile properties in the steel EUROFER 97 deformed for two

ECAP passes.

According to the results obtained in EUROFER 97 ECAP pro-

cessed via route C, it is expected that a selected combination of

routes and annealing treatments should produce a nanostructured

microstructure with enhanced mechanical properties.

4. Conclusions

The EUROFER 97 steel was processed by ECAP at 550 C for up

to four passes via route C, and the effects on the grain structure,

crystallographic texture and tensile properties were investigated.

The main results are as follows:

1) The initial microstructure of the material in the as-tempered

condition consisted of a ferrite-martensite dual phase

microstructure (volume fraction of martensite was 27 vol.%).

The microstructure contains fine subgrains of about 0.5m in

size and LABs less than 5 and second phase particles around

10vol.%. The texture was composed by several weak fibers with

their orientations into the zone axes 1 1 0, 1 1 1 and 1 1 2.

2) The first ECAP pass produced a highly elongated and shear

strained structure with fragmented grains. After two ECAP

passes a grain microstructure composed of lamellar and

equiaxed substructure was observed. With further passes the

fragmentation of the microstructure progressed giving rise to a

practically equiaxed substructure after four passes.

3) The evolutionof the microstructure uponECAP deformation was

accompanied by the development of a newtexture describedby

a family of fibers retaining the zone axes 1 1 0 and 1 1 1 after

the successive passes. The martensite phase changes to ferrite

and the fraction of LABs decreases with ECAP deformation. The

martensite fraction lowered to 5 vol.% after four ECAP passes.

4) The yield strength and tensile strength increased significantly

after deformation for two ECAP passes but decreased after

four passes. The enhanced mechanical behavior of the ECAP

deformedsteel EUROFER97 could be attributed to theformation,

refinement and texture evolution of the lamellar substructure

induced by ECAP deformation.

Acknowledgements

This work has been supported by Madrid Community through

the project TECHNOFUSION (S2009/ENE-1679) and Spanish Min-

istryof Science and Innovation (Contract ENE2008-06403-C06-04).

The authors thankthe microscopy laboratory of CENIM-CSIC for

EBSD measurements.

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