Crystallization phases of the Zr41Ti14Cu12.5Ni10Be22.5 alloyafter slow solidification

Q. Weia)

Universitat Potsdam, Institut fu¨r Berufspadagogik, Karl-Liebknecht-str. 24-25, D-14476,Golm, Germany

N. Wanderka,b) P. Schubert-Bischoff, and M-P. MachtHahn-Meitner-Institut Berlin GmbH, Glienicker Strasse 100, 14109 Berlin, Germany

S. FriedrichUniversitat Potsdam, Institut fu¨r Berufspadagogik, Karl-Liebknecht-str. 24-25, D-14476,Golm, Germany

(Received 29 November 1999; accepted 12 May 2000)

A systematic study was carried out on the equilibrium phases after slow solidificationof the Zr41Ti14Cu12.5Ni10Be22.5 alloy. The crystalline microstructure of the slowlycooled melt of the alloy shows “polygons” and “plates” embedded in a fine-grainedtwo-component matrix. To analyze the crystal structure of the different components,microdiffraction technique combining convergent beam electron diffraction andconventional selected-area electron diffraction were used. The stoichiometry of thesephases was confirmed by field ion microscopy with atom probe and energy-dispersivex-ray analysis in a transmission electron microscope. The polygons were determined tobe cubic (a 4 1.185 nm) with space groupFm3m (cF116). The plates were found tobe tetragonal (a 4 0.37 nm,c 4 1.137 nm) with space groupI4/mmm(tI6). Itscomposition is (Cu + Ni)(Zr + Ti)2. One phase of the fine-grained two-componentmatrix was rich in Ti and poor in Be; the other one was rich in Be and poor in Ti. TheTi-rich phase was determined to be hexagonal (a 4 0.536 nm,c 4 0.888 nm) withspace groupP63/mmc.

I. INTRODUCTION

One way to design multicomponent metallic alloy sys-tems with good glass-forming ability, such as ZrTiCu-NiBe alloys1 is to combine binary and ternary systems ofearly (e.g., Zr, Ti, Hf) and late transition metals (e.g., Cu,Ni, Co) and simple metals (e.g., Be, Al) with deep eu-tectics and large differences of the atomic sizes for dif-ferent alloy components. Such bulk metallic glassesshow strong resistance against crystallization in the su-percooled liquid state within a wide temperature rangeabove glass transition. The Zr41Ti14Cu12.5Ni10Be22.5

bulk glass has been investigated intensively with respectto amorphous phase separation and crystallization duringheat treatment2–7; however, only few investigations ofthe equilibrium phases exist.7,8 The aim of this work is tostudy the morphology, chemical composition, and struc-ture of the crystalline phases after slow solidification ofthe Zr41Ti14Cu12.5Ni10Be22.5 alloy.

For composition analysis of the different phases ofa heterogeneous microstructure, energy dispersivex-ray analysis in a transmission electron micro-scope (TEM/EDX) was applied successfully after care-ful sample preparation. As Be cannot be detected byEDX, an additional analysis by field ion microscopy withatom probe (FIM/AP) was carried out, which alloweda full analysis of all the components, even for verysmall crystals.

X-ray diffraction (XRD) techniques for structure de-termination have been used frequently because of theirhigh precision compared to the conventional electron dif-fraction methods.9 However, it is difficult to measure thestructure of small volume fractions of crystalline phasesand of small crystals by these techniques. Moreover, ifthe microstructure contains several unknown compli-cated phases, the structure of the respective phases mustbe analyzed locally. In recent years convergent beamelectron diffraction (CBED) has been adopted for iden-tifying unknown phases in small regions (<1mm).10 Thistechnique reveals three-dimensional symmetry informa-tion which enables rapid determination of the crystallo-graphic point group. When this technique is combinedwith selected-area diffraction (SAED) patterns, one can

a)Present address: Max-Planck-Institut fu¨r MikrostrukturphysikHalle, Weinberg 2, 06120 Halle, Germany.

b)e-mail: wanderka@hmi.de

J. Mater. Res., Vol. 15, No. 8, Aug 2000 © 2000 Materials Research Society 1729

discern possible space groups of the crystal structure.11

However, the CBED method usually requires suitablespecimens. Many specimens, especially those composedof fine crystals or crystals with large lattice parameters,give relatively poor CBED patterns showing little or nointensity variations within the disks. As a result, pointgroup identification becomes impossible under these cir-cumstances. An alternative technique is microdiffrac-tion.12,13 With this method the disk diameter in CBEDpattern can be reduced by using a nearly parallel electronbeam, thereby improving the angular resolution and re-ducing the diffuse scattering in the diffraction pattern.Considering both, geometrical symmetry (reflection po-sition) and intensity symmetry of the zero-order Lauezone (ZOLZ) and first-order Laue zone (FOLZ) patterns,one can identify both the point and space groups of acrystal phase. A systematic procedure to determine thecrystal point and space group using microdiffraction pat-terns was proposed by Morniroliet al.12,13In the presentpaper notations and terms are used according to theirdefinitions.12,13

The microdiffraction technique combining both CBEDand SAED was applied to determine the crystal structuresof the unknown phases. Combining this structural infor-mation with the stoichiometry of the phases supplied bycompositional analysis of TEM/EDX and FIM/AP, theequilibrium phases in Zr41Ti14Cu12.5Ni10Be22.5 alloywere identified. Additional XRD spectra were used.

II. EXPERIMENTAL

The alloy was prepared by alloying a master alloyfrom Zr (99.5%) and Be (99%) and by melting it togetherwith pure Ti, Ni, and Cu (99.99% each) in a specialinduction levitation melting device under purified argon(oxigen partial pressure 10−9 Pa). The resulting amor-phous ingot was encapsulated in an argon-filled sealedsilica tube, then melted and held at 1300 K for 6 h in atube furnace, and finally cooled with a rate of 0.4 K/s.Slices approximately 1 mm thick were cut by a diamondsaw from the resulting alloy rod (10-mm diameter). Theywere mechanically ground and polished to a thickness ofabout 0.3 mm. An ultrasonic disc cutter was used to cutthe samples of 3 mm in diameter, which were ion beammilled to transparency. The specimens were very brittleand had to be prepared with great care. To trace thedifferent phases, it was necessary to combine optical andelectron microscopic (TEM) observations. Details of thepreparation procedure are published elsewhere.14 Theelectron diffraction pattern was obtained at 100 kV on aPhilips EM400. The small convergence angle was ob-tained by using a 50-mm condenser aperture, and the spotsize was in the range of 10–100 nm. The TEM/EDX wascarried out on a Philips CM30. FIM/AP was used tomeasure the concentration of Be, because this element

cannot be detected with EDX. The FIM tips with a tipradius of about 100 nm were prepared from crystal frag-ments by mechanical grinding and ion milling.15 TheXRD spectra were taken from different cross sections ofthe alloy rod with Cu Ka radiation in theu–2u configu-ration by use of a Bruker AXS D8 diffractometerequipped with a graphite monochromator and a scintil-lation counter forl 4 0.05 to 0.3 nm.

III. RESULTS AND DISCUSSION

A. Morphology and composition

Figure 1 shows an optical micrograph of the multi-phase microstructure. The microstructure shows “poly-gons” and “plates” embedded in a fine-grained twocomponent matrix. According to their morphology thedifferent phases are named polygons (A), plates (B) andmatrix I and II (C). The crystals of the different phasesare of different sizes ranging from the subnanometerscale to several hundred micrometers. It has been shownthat the size depends on the cooling rate16 and on theundercooling of the melt.7,8 Even under the slow coolingconditions in the present case the distribution of the dif-ferent crystalline phases and the size and the alignment ofthe crystals depict the history of the solidification of themelt. For example, there are many more polygons in theupper part of the alloy rod, whereas at the bottom of therod the fine-grained matrix is coarser. Thus the volumefractions of the different phases cannot be determined.Moreover, the complicated crystallization sequence andimpeded convection of the highly viscous melt may leadto local deviations from the equilibrium compositionwhich modify the matrix microstructure.17

FIG. 1. Optical micrograph of the microstructure obtained by slowcooling of the liquid Zr41Ti14Cu12.5Ni10Be22.5melt. According to theirmorphology the different components are named (A) polygons, (B)plates, and (C) fine-grained two-phase matrix.

Q. Wei et al.: Crystallization phases of the Zr41Ti14Cu12.5Ni10Be22.5 alloy after slow solidification

J. Mater. Res., Vol. 15, No. 8, Aug 20001730

The relative composition (without Be %) of eachphase measured by TEM/EDX and the composition ofthree phases measured by FIM/AP are presented inTable I. The result of FIM/AP shows that the fine-grained two-component matrix is composed of twophases, one is rich in Be and poor in Ti, while the otherone is rich in Ti and poor in Be. The plates (B) arepractically free of Be and the ratio of (Ni + Cu):(Zr + Ni)is about 1:2. A Zr2Cu-type phase was also found in thesame alloy after isothermal crystallization in the under-cooled melt.8 It has been further stated by the same au-thors that a MgZn2-type Laves phase crystallizes fromthe liquid melt; howeveer, no such phase could be ob-served during the present investigation.

The polygons could not be analyzed with FIM/AP be-cause of difficulties with the sample preparation. Fromthe dark appearance of the polygons in the SEM image,17

it is supposed that the polygons are rich in low atomicorder elements, e.g., Be. Concentration fluctuations ofthe constituents Zr and Ti in the crystals without signifi-cant change of the lattice parameter were revealed bycombined TEM/EDX and TEM/SAD microanalysis,14

indicating that the polyhedric/cubic phase can exist in awide concentration range.

B. Structure

1. Polygons

Figures 2(a)–2(c) show [111], [001], and [011] micro-diffraction patterns taken from polygons. The highest netsymmetries obtained from these patterns are 4mmin [001] [Fig. 2(a)] and 6mm in [111] [Fig. 2(b)],which according to Table 7 of Ref. 12 corresponds to acubic system. To characterize the Bravais lattice andglide plane, identification of the⟨100⟩ and ⟨110⟩ zoneaxis patterns (ZAP) is required.12 On the [001] ZAP[Fig. 2(a)], a shift between the nets of reflections situatedin the ZOLZ and in the FOLZ implies that the Bravaislattice cannot be primitive. Furthermore, the smallestsquares drawn in the ZOLZ and in the FOLZ are iden-

tical. This means that there is no periodicity differencebetween ZOLZ and FOLZ reflection nets. According toFig. 9(d) in Ref. 12, the corresponding individual partialextinction symbol is eitherI- . . or F- . . . Thedistinctionbetween theI andF Bravais lattices should be combinedwith the additional observation of the⟨011⟩ ZAP. The[011] ZAP [Fig. 2(c)] exhibits a centered rectangle net ofthe reflections with a net 2mmsymmetry in ZOLZ. Thelack of the FOLZ in this pattern satisfies the structurefactor extinction conditions for a face-centered lattice(h + k, h+ l, k + l 4 odd).12 Comparison with Fig. 9(d)of Ref. 12 leads to the unique determination of the facecentered Bravais lattice with partial extinction symbolF . .-. Furthermore, no forbidden reflection was observed

FIG. 2. Microdiffraction pattern of polygons: (a) [001] zone-axisshowing 4mm net symmetry in ZOLZ, (b) [111] zone axis showing6mmnet symmetry in ZOLZ and 3mm intensity symmetry in FOLZ,(c) [110] zone axis showing 2mmsymmetry in ZOLZ.

TABLE I. Composition of the equilibrium phases of the Zr41Ti14Cu12.5Ni10Be22.5alloy as measured by TEM/EDX (without consideration of Be)and FIM/AP. The error bars for EDX analysis areø1 at.%, and for FIM/AP they are of magnitude 2s.

State Analyses

Chemical composition (at.%)

Zr Ti Cu Ni Be

Amorphous nominal 41 (53) 14 (18) 12.5 (16) 10 (13) 22.5 (0)FIM/AP 46.4 ± 1.3 14.3 ± 0.9 7.3 ± 0.6 10.7 ± 0.8 21.3 ± 1.1

Polygons EDX (41) (11) (31) (17)Plates EDX (59) (9) (28) (4)

FIM/AP 49.0 ± 4.0 8.8 ± 2.4 35.6 ± 3.2 5.4 ± 1.9 1.2 ± 0.9Matrix I EDX (23) (39) (17) (21)

FIM/AP 34.5 ± 5.4 37.4 ± 5.1 10.6 ± 3.1 9.8 ± 3.6 7.3 ± 2.5Matrix II EDX (45) (16) (17) (22)

FIM/AP 38.3 ± 1.5 7.1 ± 0.7 10.3 ± 0.8 8.8 ± 0.7 35.5 ± 1.5

Q. Wei et al.: Crystallization phases of the Zr41Ti14Cu12.5Ni10Be22.5 alloy after slow solidification

J. Mater. Res., Vol. 15, No. 8, Aug 2000 1731

in the [110] zone axis along [001] which excludes theexistence of a screw axis being parallel to⟨001⟩. Frommeasurements of diffraction spot distances using [111],[001] and [011] ZAPs the lattice parameter of this phasewas calculated to bea 4 1.185 nm.

A careful examination of the intensity of a⟨111⟩ ZAPshows that the beam intensity is compatible with a6mmsymmetry in ZOLZ but only with a 3m symmetryin FOLZ. Therefore, the whole pattern (WP) can onlyhave a 3m symmetry. According to the Table 4 inRef. 12, the point group corresponding to such a sym-metry ism3m,which belongs to a centrosymmetric crys-tal. The possible space group in this case could be eitherFm3m, Fm3c, Fd3m, or Fd3c. Considering the partialextinction symbols, as mentioned above, one can excludethe existence of glide planesd // (001) andc // (110). Itis concluded, therefore, that the space group of the poly-gons must beFm3m.

Examples for this space group with a similarly largelattice parameter as the polygons are the Be-richBe15Ni8Zr6, Be15Ni8Ti6, and Be15Cu8Zr6, which corre-spond to the Mn23Th6 (cF116) structure type.18

2. Plates

The tetragonal structure of the plates was determinedby tilting the specimen around several zone axes in theSAED mode and by indexing the corresponding SAEDpatterns. The lattice parameters area 4 0.34 nm andc 4 1.137 nm.

Figure 3(a) shows the [100] zone axis microdiffrac-tion pattern. Both ZOLZ and FOLZ reflections have a(2mm), 2mmnet, and (2mm), 2mm ideal symmetries andexhibit a centered rectangle pattern. The absence ofZOLZ/FOLZ periodicity difference indicates that thereis no glide plane perpendicular to the [100] direction.According to Fig. 9(c) in Ref. 12, the partial extinctionsymbol isI .-. .

CBED was used to identify the point group of the platecrystal. A [110] CBED ZOLZ pattern in Fig. 3(b) exhib-its a 2mmsymmetry. The FOLZ reflections are weak andfar away from the center of the screen. To observe them,the specimen was carefully tilted along the mirrorsm1and m2 until FOLZ areas appear on the pattern.Figure 3(c) shows the FOLZ pattern along themirror m1. The intensity of the FOLZ pattern presents a2mm symmetry. The 2mm WP symmetry observed on[110] ZAP corresponds to the point group 4/mmm asgiven in Table 4 in Ref. 12.

The possible space groups satisfying such conditionsare listed in Table II together with the reflection condi-tions. A careful examination of the [100] SAED pattern[Fig. 3(a)] shows that reflection planes of the form (00l)are present for alll 4 2n which, referring to Table II,eliminates theI4/amdcase. Thus the space group for theplates must beI4/mmm.

FIG. 3. (a) [100] zone axis microdiffraction pattern of plates with(2mm), 2mmnet symmeries in ZOLZ and (2mm), 2mm ideal symme-tries in FOLZ, obtained by tilting the specimen along the mirrorsm1and m2; (b) [110] CBED ZOLZ pattern with 2mm symmetry andFOLZ pattern with a 2mmsymmetry, obtained by tilting the specimenalong the mirrorm1.

Q. Wei et al.: Crystallization phases of the Zr41Ti14Cu12.5Ni10Be22.5 alloy after slow solidification

J. Mater. Res., Vol. 15, No. 8, Aug 20001732

The corresponding FIM/AP analysis of this phaseshows that it contains practically no Be (Be <1 at.%) andthat the ratio of (Zr + Ti) to (Cu + Ni) is 2:1. Therefore,this phase is of the Zr2Cu type, which is a dominatingphase of the Zr(Ti)–Cu(Ni) boundary system. The addi-tions of Ti and Ni may cause slightly different latticeconstants in comparison to Zr2Cu.

3. Matrix I and II

As mentioned above the matrix I and II consists oftwo phases, one of them is rich in Be and poor in Ti. Theother is rich in Ti and poor in Be. The structure of theTi-rich phase was determined to be hexagonal by usinga series of SAED patterns. The lattice parameters area 4 0.536 nm andc 4 0.888 nm.

Figure 4(a) shows the [1121] zone axis microdiffrac-tion pattern for the Ti-rich phase. Both the geometricaland the intensity symmetry of the ZOLZ reflection netsare 2mm. But the whole pattern has only anm symmetry,if the intensity of FOLZ reflection nets is also taken intoaccount. According to Table 4 in Ref. 12, the corre-sponding point group in a hexagonal system satisfyingsuch a condition is 6/mmm. The possible space groupsare thereforeP6/mmm, P63/mmc, P63/mcm,or P6/mcc.

To determine whether a screw axis exists, the specimenwas tilted around the [0001] direction. Figures 4(b)–4(d)show [1120], [4150], and [1010] ZAPs. By tilting from[1120] to [1010], the intensity of the (000l, l 4 2n + 1)reflections is strongly reduced and eventually vanishes.This suggests that a 63 screw axis parallel to [0001]exists, which produces extinction. Such forbidden reflec-tions are located along the row parallel to the screw axis.The forbidden reflections (000l, l 4 2n + 1) may appearby double diffraction12 and can only be distinguishedfrom the allowed reflections by tilting around the [0001]axis. In this wayP6/mmmand P6/mcc were excluded.Furthermore, the examination of the [1120] patternshows that reflection planes of the form (hh0l) are pres-ent for all l, which from Table 3.2 in Ref. 12 eliminatesthe P63/mcm case, in which the reflection conditionl 4 2n in (hh0l) exists. Consequently the space group ofthis crystal must beP63/mmc. However, the actual com-position of this phase (cf. Table 1) does not allow itsdescription in terms of any known structure type.19

The structure of the Ti-poor phase could not be iden-tified because of difficulties with the sample preparation.Two of the three phases identified by the TEM analysis,plates and matrix I, can be also found in the XRD spec-trum in Fig. 5. The identification of the proper

TABLE II. Possible space groups and the reflection conditions forthe plates.

Space group

Reflecting planes

00l 0kl

I4/mmm l4 2n k+ l 4 2nI4/amd l4 4n k+ l 4 2n

FIG. 4. Microdiffraction pattern of the hexagonal, Ti-rich phase of thefine-grained two-phase matrix: (a) [1121] zone axis microdiffractionpattern showing (2mm) ideal symmetry in ZOLZ andm symmetry inFOLZ, (b) [1120] zone axis, (c) [4150] zone axis, (d) [1010] zone axis.

FIG. 5. X-ray diffraction spectrum of the slowly solidifiedZr41Ti14Cu12.5Ni10Be22.5melt (Cu Ka, l 4 1.541Å). The Bragg peaksof two of the different phases are indicated.

Q. Wei et al.: Crystallization phases of the Zr41Ti14Cu12.5Ni10Be22.5 alloy after slow solidification

J. Mater. Res., Vol. 15, No. 8, Aug 2000 1733

Bragg peaks was only possible because the structure ofthe respective phases is known from the local analysis ofdiscrete crystals. Thus no Bragg peaks could be associ-ated with the phase matrix II. Moreover, only qualitativeconclusions can be drawn from the XRD spectrum, be-cause of the inhomogeneity of the microstructure and atexture caused by the alignment of the crystals duringsolidification (e.g., the plates). In particular the diffrac-tion pattern of the polygons could not be discovered inthe XRD spectrum. Although these crystals can be large(see Fig. 1), the volume fraction is rather small and theyare mainly concentrated at the top of the alloy rod.20

IV. SUMMARY

During slow cooling, the Zr41Ti14Cu12.5Ni10Be22.5

melt crystallizes into a four-phase microstructure (poly-gons and plates embedded into a fine-grained two-phasematrix). The crystal structure, point and space groups,and the compositions of three of these phases were de-termined respectively by using microdiffraction combin-ing CBED and SAED methods as well as by use ofTEM/EDX and FIM/AP analysis.

The first phase (polygons) was identified to be face-centered-cubic with space groupFm3m (cF116) and alattice parametera 4 1.185 nm. It is probably relative tothe phases Be15Ni8Zr6, Be15Ni8Ti6 and Be15Cu8Zr6.

The second phase (plates) is tetragonal with spacegroup I4/mmm and lattice parametersa 4 0.37 nmand c 4 1.137 nm. The composition of this phase isdetermined to be (Cu + Ni)(Zr + Ti)2, which is similarto CuZr2 (tI6), with a slight difference of the latticeparameters.

One phase of the fine-grained two-phase matrix is richin Ti and poor in Be. The other one is rich in Be and poorin Ti. The crystal structure of the Ti-rich phase is hex-agonal with space groupP63/mmcand lattice parametersa 4 0.536 nm andc 4 0.888 nm.

ACKNOWLEDGMENTS

The authors thank Dr. W. Mieckeley and Mr. W.Ronnfeld for alloy preparation and realization of the so-lidification experiments, Dr. M. Mu¨ller for performingthe XRD analysis, Dr. Mukherji for valuable discussionsand suggestions, and Prof. Dr. H. Wollenbereger and Dr.V. Naundorf for the critical reading of the manuscript.

REFERENCES

1. W.L. Johnson, Mater. Sci. Forum225–227,35 (1996).2. A. Wiedenmann, U. Keiderling, M-P. Macht, and H. Wollen-

berger, Mater. Sci. Forum225–227,71 (1996).3. M-P. Macht, N. Wanderka, A. Wiedenmann, H. Wollenberger,

Q. Wei, H.J. Fecht, and S.G. Klose, Mater. Sci. Forum225–227,65 (1996).

4. S. Schneider, P. Thiagarajan, U. Geyer, and W.L. Johnson,Physica B241–243,918 (1998).

5. N. Wanderka, Q. Wei, I. Sieber, U. Czubayko, and M-P. Macht,Mater. Sci. Forum312–314,369 (1999).

6. N. Wanderka, Q. Wei, R. Dole, M. Jenkins, S. Friedrich, M-P.Macht, and H. Wollenberger, Mater. Sci. Forum269–272,773(1998).

7. H-J. Fecht, inStructure and Dynamics of Glasses and GlassFormers,edited by C.A. Angell, K.L. Ngair, J. Kieffer, T. Egami,and G.U. Nienhaus (Mater. Res. Soc. Symp. Proc.455,Pittsburgh,PA, 1997), p. 455.

8. J. Schroers, R. Busch, A. Masuhr, and W.L. Jonson, Appl. Phys.Lett. 74, 2806 (1999).

9. H.P. Klug and L.E. Alexander,X-ray Diffraction Procedures(John Wiley and Sons, New York, 1974).

10. B.F. Buxton, J.A. Eades, J.W. Steeds, and G.M. Rackham, Philos.Trans. R. Soc. A284,171 (1976).

11. B.G. Demczyk and S.F. Cheng, J. Magn. Mater.88, 376 (1990).12. J.P. Morniroli and J.W. Steeds, Ultramicroscopy45, 219 (1992).13. A. Redjaimia and J.P. Morniroli, Ultramicroscopy53,305 (1994).14. D. Muhlhausen, P. Schubert-Bischoff, Q. Wei, and M-P. Macht,

in Progress in Metallography,edited by M. Kurz and M.M. Pohl(special edition of the Practical Metallography 27, Informations-gesellschaft Verlag Oberursel/FRG, 1995), p. 291.

15. N. Wanderka, P. Schuber-Bischoff, V. Naundorf, M-P. Macht,and H. Wollenberger, inProceedings of the 11th european con-gress on electron microscopy, EUREM’96, T10,edited by W.Baumeister and D. Cottell (EUREM ’96 U.C.D. Belfield, Dub-lin 4, Ireland, 1996).

16. M-P. Macht, N. Wanderka, A. Wiedenmann, H. Wollenberger,Q. Wei, S. Klose, A. Sagel, and H-J. Fecht, inThermodynamicsand Kinetics of Phase Transformations,edited by J.S. Imn,B. Park, A.L. Greer, and G.B. Stephensen (Mater. Res. Soc.Symp. Proc.398,Pittsburgh, PA, 1996), pp. 375–380.

17. M-P. Macht, N. Wanderka, Q. Wei, I. Sieber, N. Deyneka,Pro-ceedings of the tenth International Conference on RapidlyQuenched and Metastable Materials (RQ10), 23.8.–27.8,editedby K. Chattopadhyay and S. Ranganathan (Bangalore, India, inpress).

18. E. Ganglberger, H. Nowotny, and F. Benesowsky, Monatsh.Chem.96, 1206 (1965).

19. W.B. Pearson,A Handbook of Lattice Spacings and Structures ofMetals and Alloys(Pergamon Press, Oxford, New York, 1967),Vol. 2, p. 93.

20. M-P. Macht, Q. Wei, N. Wanderka, I. Sieber, and N. Deyneka,Mater. Sci. Forum343–346,173 (2000).

Q. Wei et al.: Crystallization phases of the Zr41Ti14Cu12.5Ni10Be22.5 alloy after slow solidification

J. Mater. Res., Vol. 15, No. 8, Aug 20001734