NEUTRON DIFFRACTION STUDY OF AMORPHOUS BINARY ALLOYS

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AMORPHOUS BINARY ALLOYS

T. Mizoguchi, N. Nishioka, S. Yamada, T. Suemasa, S. Yoda, N. Akutsu, H.

Narumi, T. Kudo, M. Akimitsu, N. Watanabe, et al.

To cite this version:

T. Mizoguchi, N. Nishioka, S. Yamada, T. Suemasa, S. Yoda, et al.. NEUTRON DIFFRACTION

STUDY OF AMORPHOUS BINARY ALLOYS. Journal de Physique Colloques, 1982, 43 (C9), pp.C9-

659-C9-670. �10.1051/jphyscol:19829131�. �jpa-00222438�

JOURNAL DE PHYSIQUE

Colloque C9, supplement au n°12, Tome 43, deeembre 1982 page C9-659

NEUTRON DIFFRACTION STUDY OF AMORPHOUS BINARY ALLOYS

T. Mizoguchi, N. Nishioka, S. Yamada, T. Suemasa, S. Yoda, N. Akutsu, H. Narumi, T. Kudo, M. Akimitsu, N. Watanabe* , M. Nishi** and K. Motoya**

Faculty of Scienoe, Gakushuin University, Mejiro, Toshimaku, Tokyo 171, Japan

*National Laboratory for High Energy Physios, Tsukuba, Ibaraki 305, Japan

**Institute for Solid State Physios, Roppongi, Minatoku, Tokyo 106, Japan

Résumé.- Pour effectuer une investigation structurelle des allia- ges amorphes, des expériences de diffraction des neutrons TOF ont été réalisées avec une source de neutrons puisée au Laboratoire National de Physique à Haute Energie du Japon. Ce résumé présen- te un rapport sur les résultats obtenus sur des alliages amorphes binaires à 3d transition en base Zr, spécialement le Ni

x

Zri_

x

d' une large plage de composition (0,18^x^0,90). Des alliages Ni0,36

z

ro,64 à substitution isotopique ont été mesurés pour ob-

tenir les structures partielles. Dans cet alliage amorphe, il semble exister un ordre chimique à courte portée, résultant en une forte corrélation de paire Zr-Ni et une faible corrélation au voi- sin le plus proche Ni-Ni. Pour les alliages amorphes Fe-B ferro- magnétiques, la diffraction à neutrons polarisés donne des infor- mations sur les structures partielles.

Abstract.- For structural investigation of amorphous alloys TOF neutron diffraction experiments were carried out with the pulse neutron source at the National Laboratory for High Energy Physics in Japan. Results on Zr base 3d transition metal binary amorphous alloys especially N i

x

Z r

1

_

x

of wide composition range (0.18 < x

< O.90) are reported. Isotope substituted N i ^ g

Z r

.g4 alloys were measured to get the partial structures. There seems to exist a

chemical short range order in this amorphous alloy, resulting in a sharp Zr-Hi pair correlation and poor Ni-Ni nearest neighbor correlation. For ferromagnetic Fe-B amorphous alloys, polarized neutron diffraction gives information about the partial structures.

1. Introduction.- Neutron diffraction experiments are powerful tools for the structural study of amorphous materials for the following rea- sons.

1) The interaction between neutrons and nuclei is so short-ranged that the nuclear scattering amplitude is independent of Q = 4 it sin6/A, where 6 is the scattering angle and X is the wave length of neutrons.

Useful structural information can be obtained directly from the diffrac- tion pattern of wide range. Time of flight (TOF) method with pulse neu- tron source is especially advantageous as it covers a wide range of Q.

2) In order to get partial structures in binary or multi-component a- morphous materials, which are stable practical systems in most cases, we can compare and combine the diffraction patterns of isotope substi- tuted samples of the same chemical composition. It is certain that iso- topes have a different sensitivity for neutrons but the same chemical effects for partial structure in the alloys.

3) For ferromagnetic systems in which the magnetic moment of consti- tuent elements is different, polarized neutron diffraction can give information for partial structures owing to the contributions of the

Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:19829131

magnetic s c a t t e r i n g . I n t h i s c a s e , we can i n v e s t i g a t e an i d e n t i c a l sam- p l e i n t h e i d e n t i c a l e x p e r i m e n t a l c o n d i t i o n s by f l i p p i n g t h e p o l a r i z a - t i o n of n e u t r o n s p i n s . T h i s i s i m p o r t a n t because t h e r e i s an e s s e n t i a l problem t h a t t h e s t r u c t u r e of amorphous s o l i d s i s determined n o t o n l y by t h e chemical composition, b u t may b e modified by t h e f a b r i c a t i o n c o n d i t i o n s and s t r u c t u r e r e l a x a t i o n a s t h e y a r e n o n - e q u i l i b r i u m s t a t e s of m a t t e r s .

TOF n e u t r o n d i f f r a c t i o n e x p e r i m e n t s have been c a r r i e d o u t a t room tem- p e r a t u r e u s i n g t h e

H I T

( h i g h i n t e n s i t y t o t a l s c a t t e r i n g ) s p e c t r o m e t e r w i t h t h e p u l s e n e u t r o n s o u r c e (KENS) i n s t a l l e d t o t h e b o o s t e r of p r o t o n a c c e l e r a t o r of t h e N a t i o n a l L a b o r a t o r y f o r High Energy P h y s i c s . The amorphous b i n a r y a l l o y s s o f a r measured a r e Fe90Zr=10, Cox Z r l - , (x

=

0 . 3 6 and 0 . 9 0 ) ,

N i , Z r l - ,

( x

=

0 . 1 8 , 0.24, 0 . 3 4 ,

0 . 3 6 ,

0 . 6 4 and 0 - 9 0 ) , C u , 3 6 Z r a 6 4 ,

C U

x Tll-,

( X =

0 . 4 , 0 . 5 and 0 . 6 ) and Mg.70ZQ30.

I n o r d e r t o i n v e s t i g a t e t h e p a r t i a l s t r u c t u r e s of b i n a r y amorphous a l - l o y s , i s o t o p e 6 0 i ~ i and 6 5 ~ u were s u b s t i t u e d i n

N i x Z r l - x

( x

=

0 - 3 6 , 0 . 6 4 ) and CuxTil-, (x

=

0 . 4 , 0 . 5 and 0 . 6 ) , r e s p e c t i v e l y . Here some r e - s u l t s of

Z r

based 3d t r a n s i t i o n m e t a l s amorphous b i n a r y a l l o y s a r e shown.

P o l a r i z e d

neutron

d i f f r a c t i o n of b i n a r y f e r r o m a g n e t i c amorphous ?ex

B1-x

a l l o y s (x = 0 . 8 1 and 0.84) was c a r r i e d o u t w i t h PANS1 s p e c t r o m e t e r of ISSP i n s t a l l e d t o t h e JNR2 s t e a d y s t a t e n u c l e a r r e a c t o r i n t h e J a p a n Atomic Energy Research I n s t i t u t e . An amorphous F$a0G2 a l l o y was s t u d i e d by Lamparter e t a l . who combined X-ray d i f f r a c t i o n an3 u n p o l a r i z e d neu- t r o n d i f f r a c t i o n w i t h n a t u r a l Fe and i s o t o p e 5 7 ~ e s u b s t i t u t e d samples.

2. Experimental p r o c e d u r e . - The amorphous a l l o y s were p r e p a r e d by r a p i d quenching from t h e m e l t b a s i n g l e r o l l t e c h n i q u e i n argon atmosphere.

Amorphous a l l o y r i b b o n s o r a b o u t

3 U

- 5oum t h i c k and Lmm wlde were c u t i n t o s m a l l p i e c e s and packed i n t o a c y l i n d r i c a l sample c e l l of 8mm i n d i a m e t e r made of t h i n (25pm) vanadium f o i l . The amount of samples were u s u a l l y 2 - 49 and e f f e c t i v e sample h e i g h t I n t h e c e l l was roughly

2 - 4cm.

P u l s e d n e u t r o n s o u r c e u t i l i z e s t h e p u l s e d p r o t o n beam from t h e 500MeV b o o s t e r a s an i n j e c t o r f o r t h e 12GeV p r o t o n s y n c h r o t r o n a t t h e N a t i o n a l L a b o r a t o r y f o r High Energy P h y s i c s . During normal o p e r a t i o n of t h e ac- c e l e r a t o r , 38 p r o t o n beam p u l s e s , each of which c o n t a i n s a b o u t 6 x 1011 p r o t o n s i n 50 n s e c p u l s e w i d t h , w i t h i n each main r i n g r e p e t i t i o n pe- r i o d of 2.4 s e c a r e a v a i l a b l e . The l a y o u t of B o o s t e r U t i l i z a t i o n F a c i - l i t y i s shown i n F i g . 1 / I / .

Neutrons o f t h e r m a l and e p i t h e r m a l r a n g e a r e provided by s p a l l a t i o n i n a t u n g s t e n t a r g e t w i t h moderator of p o l y e t h y l e n e a t room t e m p e r a t u r e and Be r e f l e c t o r assembly. The c o n v e r s i o n r a t i o was a b o u t 3 x

( n e u t r o n / s t r . p r o t o n ) which p r o v i d e s a b o u t 5-7 x 1014 (n/cm-sec-eV) t h e r m a l n e u t r o n s (8lmeV) on t h e moderator s u r t a c e /2/.

For TOF n e u t r o n d i f f r a c t i o n of t h e amorphous a l l o y s , t h e High I n t e n s i t y T o t a l s c a t t e r i n g

( H I T )

s p e c t r o m e t e r was used.

A

l a y o u t o f t h e s p e c t r o - m e t e r i s d e p i c t e d i n F i g . 2 /3/. The sample i s mounted a t t h e c e n t e r of a l a r g e s c a t t e r i n g chamber which i s e v a c u a t e d in o r d e r t o a v o i d a i r s c a t t e r i n g . The i n c i d e n t f l i g h t p a t h l e n g t h , L1, t h a t i s , t h e Q i s t a n c e between t h e p u l s e d n e u t r o n s o u r c e and t h e sample i s 5,053m. I n c i d e n t beam i s c o l l i m a t e d w i t h s l i t s of s i n t e r e d 1 ° ~ 4

C

p l a t e s .

S c a t t e r e d n e u t r o n s were d e t e c t e d s i m u l t a n e o u s l y by twenty He-3 c o u n t e r s

( 0 , 5 " i n d i a m e t e r , 12" l o n g and f l l l e d t o 20

atmospheric

p r e s s u r e )

around t h e sample. Normally t h e c o u n t e r s l o c a t e d a t t h e s c a t t e r i n g

a n g l e 2 8

=

13.3', 24.6', 31-5' and t h o s e which a r e a r r a n g e d i n t h e

t i m e f o c u s s i n g geometry i n c o u n t e r banks a t 2 0 = 5 0 ° , 90' and 155O a r e

used. The lower a n g l e c o u n t e r s have a p e r t u r e s which l i m i t t h e i r a c t i v e

h e i g h t t o m a i n t a i n t h e momentum r e s o l u t i o n . The r e s o l u t i o n o f t h e spec-

t r o m e t e r was checked by measuring Bragg d i f f r a c t i o n s from a S i powder

sample.

I t

was a b o u t 0.6

%

a t h i g h

Q

f o r t h e back s c a t t e r i n g c o u n t e r s ,

1 - 3

%

f o r t h e medium a n g l e c o u n t e r s and a b o u t 10

%

f o r foward coun- t e r s . T h i s may be improved by l i m i t i n g t h e a c t i v e l e n g t h of c o u n t e r s a t t h e expense of a r e d u c t i o n i n t h e c o u n t i n g r a t e .

The n e u t r o n s i g n a l s from e a c h d e t e c t o r p a s s t h r o u g h a p r e i a m p l i f i e r , a main s h a p i n g a m p l i f i e r and a d i s c r i m i n a t o r i n slow

N I M

mode. They a r e t h e n c o n v e r t e d t o f a s t l o g i c s i g n a l s and f e d i n t o h i g h speed m u l t i c h a n - n e l t i m e a n a l y s e r s which t r i g g e r e d s y n c h r o n o u s l y w i t h t h e b u r s t of i n - c i d e n t n e u t r o n p u l s e s . The maximum c o u n t i n g r a t e was found t o b e l i m i - t e d by t h e r e s p o n s e t i m e o f t h e e l e c t r o n i c s , e s p e c i a l l y t h e main ampli- f i e r , r a t h e r t h a n t h a t of t h e g a s p r o p o r t i o n a l c o u n t e r .

A

d e l a y l i n e c l i p p i n g a m p l i f i e r (Cambera Model 1 4 1 1 ) which h a s t h e s h o r t dead t i m e of 1 . 2 p s e c w i t h s h a p l n g t i m e of 0 . 4 y s e c i s p r e f e r r d d . The maximum d a t a a c q u i s i t i o n r a t e f o r e a c h c h a n n e l of t h e t i m e a n a l y s e r i s seve- r a l c o u n t s p e r u s e c .

F i g . 1

F i g .

2

. The l a y o u t of t h e B o o s t e r U t i l i z a t i o n F a c i l i t y i n t h e N a t i o n a l L a b o r a t o r y f o r High Energy P h y s i c s ( K E K ) .

0 0.5

,

The h i g h i n t e n s i t y t o t a l s c a t t e r i n g s p e c t r o m e t e r (HIT) i n KENS.

The s i g n a l s from e a c h c o u n t e r bank a r e accumulated i n d e p e n d e n t l y . The c h a n n e l width of t h e t i m e a n a l y s e r s was u s u a l l y chosen a s l i s t e d i n T a b l e

I .

s c a t t e r i n g a n g l e 150 93 5 0 31.5 24.6 13.3

1 - 512 c h a n n e l 2 2 4 4 4 4

513 - 1024 c h a n n e l 4 4 8 8 8 8

Q

min 5.4 4.0 1.2 0:79 0462 0 . 3 4

T a b l e I. Channel w i d t h of t h e t i m e a n a l y s e r i n u s u a l measurements.

Q =

4 n s i n e / A v a l u e s f o r 1024 t h c h a n n e l a r e a l s o shown f o r each d e t e c t o r .

The wave-length, X I of n e u t r o n s i s simply c a l c u l a t e d a c c o r d i n g t o t h e de B r o g l i e r e l a t i o n ,

X = h/mv

=

ht(X)/m(L1+L2) ( 1 )

where h i s t h e Planclcconstant m t h e n e u t r o n mass and t ( h ) t h e t i m e o f f l i g h t p a t h o f L1+L2,

L

b e i n g t h e d i s t a n c e between a sample and a de- t e c t o r . Measured t i m e o$ f l i g h t by t h e t i m e a n a l y s e r s h o u l d be c o r r e c - t e d w l t h t h e t r i g g e r t i m e gap and t h e a v e r a g e d e l a y t i m e d u r a t i o n , t d ( X ) , r e q u i r e d t o moderate f a s t n e u t r o n s i n t o t h e r m a l n e u t r o n s of wave

F i g . 3 . S c a t t e r i n g s p e c t r a o f a vanadium r o d of 8mrn i n d i a m e t e r a f t e r

background s u b s t r u c t i o n ( l ) , and a f t e r a t t e n u a t i o n c o r r e c t i o n

( 2 ) , background s p e c t r a ( 3 ) which a r e mainly due t o f a s t neu-

t r o n s a r e a l s o shown. Note t h a t t h e s c a l e of a h o r i z o n t a l a x i s

i s changed by a f a c t o r of two a t X

=

1.44g.

iength A. This can be estimated by experimental observation of diffrac- tion peak profiles of, for example, Si powder. For practical data ana- lysis the following experimental formula,

0

is used, where t is expressed in psec and X in A.

The spectrum of incident neutrons can be obtained by measuring the scattering from vanadium which is an almost ideal incoherent scatterer.

An observed spectrum of vanadium rod of 8 mm in diameter is shown in Fig.3 after background substruction. Absorption correction for a cylin- drical sample was calculated numerical1 /4/, The incident neutron

1

spectrum has a broad maximum around h=l and tail of epithermal region.

Pour scattering experiments, that is, scattering from a sample with a vanadium sample cell, that from empty cell only, that from the vanadium rod and background

(

no scatterer put in the place

)

were carried out successively. Observed intensity must be corrected by considering the attenuation due to the absorption by the sample and the sample cell.

They are calculated numerically /4/ for each sample.

The scattered intensities of the sample and the vanadium rod normalized by monitor counts are expressed as follows,

I = KI,, (A) N [4n(da/d~) +Dl] (3) 1,

=

KIo (A) Nv [s, + ^{M ~ ] ( 4}

Fig. 4. An example of observed scattering spectrum of an amorphous N i 36Zr alloy as a function of the time of flight after badkgrojn$ substruction (I), and after attenuation correction.

Scattering by an empty cell run is also shown (3).

where K is an instrumental constant, Ig(X) incident neutron intensity.

N and Nvare numbers of atoms in the sample and vanadium rod which

contribute scattering, respectively. Sv is the incoherent scattering

cross section of vanadium (i.e. 5.13 barn). M and Mv are the multi-

ple scattering for the sample and the vanadium rod. They are calculated

numerically /5/. Dividing I by I, we can cancel out the incident inten- sity I,(X) and the instrumental constant K. Them we have the different- ial cross section per atom of the sample as follows,

(do/dR)

=

<b2>1(Q)

= (1/4.rr) [(Nv/N) (I/IV) (SV + Mv) -MI . ⁽⁵⁾

For the polarized neutron diffraction experiment an amorphous Fe B alloy was prepared by rapid quenching from the melt. Isotope 11654 -16 was used as the natural boron contain about 20

%

of 1°B which has huge absorption cross section. Ribbon specimens of about 40pm thick and 2,5mrn wide were put side by side and laminated carefully up to 40 which was covered by a Cd window of about 20mm x 16mm. The sample was put in the magnetic field of 8kOe which align the magnetization perpendicular to the scattering vector. Polarized neutrons of wave length

1

.oZ were selected by a Heussler alloy monochromator installed in the JNR2 nuclear reactor in the Japan Atomic Energy Research Institute. PANS1 two axes spectrometer of the Institute for Solid State Physics was used to measure the diffraction pattern at room temperature by 8-28 scanning with 2' step up to 28=120~. At each step scattered intensities of polar-

ized neutrons with parallel and antiparallel spins to the magnetization of the sample were accumulated. In order to invert the neutron polari- zation a Mezei type neutron spin flipper was used.

3. Results and Discussion.- An example of observed spectrum of scattered neutrons from the amorphous Ni 36Zr is shown in Fig. 4 as a function of the time of flight or wave ~ e n g t ~ ~ ~ w h i c h is inversely proportional to Q

=

47~ sin8/A. The differential cross section which is proportional to the normalized scattered intensity I(Q) is obtained by the equation

(5). I(Q) in wide range of Q was synthesized by connecking the data obtained by different detectors at different scattering angles.

The total scattering intensity is composed of coherent scattering and the incoherent scattering.

< b 2 > 1 ( ~ )

=

<b>2s(~) + [<b2> - <b>2] (6) For binary alloy system the coherent part <b>2 S(Q) , where <b>2 means the square of averaged b and S(Q) is called the structure factor or interference function, expressed in the Faber-Ziman form.

In Fig. 5 the interference function S(Q) of amorphous Ni,Zrl-, alloys of wide composition range (0.18 < x

6

0.90) are shown. Monotonous shift of the first peak position of S(Q) from Qp =2.55E for x

=

0.18 to Q - 3.05A for x = 0.90 is observed with increasing Ni concentration x, TRIS is interpreted by that the average interatomic distance in these amorphous alloys decreases with increasing the relative number on small- er atoms of Ni than Zr.

The reduced distribution function G(r) is obtained by Fourier Trans- formation of S (Q) as follows,

The pair correlation function g(r) is related to G(r) as g (r)

=

1 + G(r)/41~rp

Q

(9)

where

p u

is the atomic number density.

The pair correlation function of the binary systems is the weighted

sum of three partial pair correlation functions as follows,

where the weighting factors are

The weighting factors for the NixZrl-, alloys are listed in Table 2.

The pair correlation functions of these amourphous alloys are shown in Fig.6. It is remarkable that for Zr rich alloys (~60.34) the nearest neighbor pair correlation function clearly splits into two peaks. The relative intensities of the two subpgaks change with composition but their position stay constant at 2.65A and 3.1A. From Table 2 we know that Wp~iMi are so small for Ni poor alloys that these two peaks corres- pond to Ni-Zr pairs and Zr-Zr pairs, respectively.

Fig. 5. The interference functions,

S ( Q ) ,

of binary amorphous Ni,Zrl-,

alloys.

Fig. 6. The pair correlation functions, g(r), of binary amorphous NixZrI-, alloys.

Table 2. The weighting factors of the partial pair correlation func- tions for amorphous Ni,Zrl-x alloys.

For Ni 90Zr alloy the first peak position r - 2.451 indicates the

Ni-Ni pair &stance as in this alloy VlhiNi is predominent. It should

be noted that the observed Ni-Zr pair &stance in these amorphous al-

loys is much smaller (95

% )

than the sum of atomic radii of Ni and Zr

Fig.7. The total pair correlation funct ns of amorphous Ni.36Zr.64 alloys with natura Ni (upper), "Ni isotope (bottom) and enriched Ni (31.7%b0Ni (middle).

estimated from Ni-Ni and Zr-Zr pair distances, respectively, suggesting a strong chemical affinity between Ni and Zr atoms in these alloys.

The total pair correlation functions of binary alloys thus obtained from the diffraction method present us significant structural infor- mation

;

however, it should be kept in mind that they are determined not only by the atomic pair distribution but also by the nuclear scat- tering length through the weighting factors as shown in Ea. (ll), (12) and (13). Therefore we get different total correlation functions or interference functions for the alloys of the same chemical composition and certainly the same atomic structure but different isotope ratio.

If we have three independent sets of experimental results we can solve

a set of three linear equations of type as Eq.

( 7 )

or (10) to get the

partial interference functions or the partial pair correlation func-

tions. This is straightforward mathematically. However, in real analy-

sis a slight error in the observed diffraction data or correction pro- cedure has serious effects on the solution of simultaneous linear eaua- t ions.

Preliminary analysis of the amorphous NixZrl-x alloys with different Ni isotope ratio suggests that there is clear nearest neighbor Ni-Zr pair and Zr-Zr pair but poor Bi-Ni nearest neighbor correlation. This tendency is in remarkable contrast to the case of an amorphous C U , ~ ~ Br.53 alloy /6/, where Cu and Zr atoms mixed almost randomly.

Fig. 8. The coherent scattering intensities of polarized neutrons with parallel spins (above) and antiparallel spins from a ferroma- gnetic amorphous Fe.84Be16 alloy.

In crystalline NiZr2, a Ni atom is surrounded by 8 Zr atoms and 2 Ni atoms, and a Zr atom is surrounded by 11 Zr atoms and 4 Ni atoms /7/.

The short range atomic order in amorphous Ni.36Zr.64 may be seen to resemble that in the lGiZr2 compound.

The coherent scattering intensities of a ferromagnetic Fegq B J ~ amor- phous alloy obtained from the diffraction pattern of polarized neutrons with parallel and antiparallel spins are shown in Fig.8 after the ne- cessary correction of the absorption and multiple scattering / 8 / . These are composed of the weighted sum of three partial interference functions,

where the subscript + or - indicate the sign of the polarization of

neutrons. In this amorphous alloy only iron atoms have a maqnetic mo-

ment, which makes additional contribution to ragnetic scattering. The

weighting factors are

and

Fig. 9. The partial interference functions, SFeFe (Q) and SFeB(Q) in an amorphous Fe .84B

.16

alloy.

The magnetic scattering amplitude, p, is given as follows, P = (ye2/2rnc2) u f (Q) (19) The value of the magnetic moment of iron in this alloy obtained is

1 . 6 5 ~ at room temperature by magnetization measurement. The calculated

magnetic form factor, f(Q), given by Watson and Freeman /9/ was used.

The numerical calculation of the weighting factor shows that W3 for B-B term is almost negligible compared to the other two. As a first approximation we tried to solve SFeFe and S F ~ B from equation (14) neglecting the third term. The results are shown in Fig.9. Fe-Fe inter- ference function resembles the observed total diffractionpattern, but Fe-B interference function is to be seen antiphase to the Fe-Fe inter- ference function. These results are mostly consistent with the results of Lamparter et al. / l o / .

Acknow1eqments.- The authors would like to express sincere thanks to

Prof. Ishikawa and Prof. Sasaki for construction of KENS facility,

Dr. T. Fukunaga for collaboration in HIT experiments and a computer

program for attenuation correction.

References .

/1/ H. Sasaki, Proceedings of the 4th International Collaboration on Advanced Neutron Source (1981) p77

/2/ Y. Ishikawa, ibid p89

/3/ N. Watanabe, T. Fukunaga, T. Shinohe, K. Yamada and T. Mizoguchi, ibid p 539

/4/ H. H. Poolman and C. J. Pings, J. Appl, . Phys. 33 (1962) 2635 /5/ I. A. Blech and B. L. Averbach, Phys. Rev. 137 (1965) A1113 /6/ T. Mizoguchi, T. Kudo et al., Rapidly Quenched Metals ¹¹¹ vo1.2

(1973) Edt. B. Cantor, The Metal Society (London) .

/7/ M. E. Kirkpatrick, D. M. Bailey and J. F. Smith,Acta Cryst. 15 (1962) 252

/8/

G.

H. Vineyard, Phys. Rev. 96 (1954) 93

/9/ R. E. Watson and A. J. Freeman, Acta Cryst. 14 (1961) 27

/lo/ P. Lamparter, W. Spepl, E. Nold, G. Rainer-Harbach and S. Steeb,

Proceedings 4th Int. Conf. on Rapidly Quenched Metals (1981)

p 343