HAL Id: jpa-00220965
https://hal.archives-ouvertes.fr/jpa-00220965
Submitted on 1 Jan 1981
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
α AND β PEAKS OF COLD WORKED AND HYDROGEN CHARGED MOLYBDENUM
N. Igata, K. Miyahara, K. Hakomori, T. Miyagi, H. Yoshida
To cite this version:
N. Igata, K. Miyahara, K. Hakomori, T. Miyagi, H. Yoshida. α AND β PEAKS OF COLD WORKED
AND HYDROGEN CHARGED MOLYBDENUM. Journal de Physique Colloques, 1981, 42 (C5),
pp.C5-61-C5-66. �10.1051/jphyscol:1981508�. �jpa-00220965�
JOURNAL DE PHYSIQUE
CoZZoque C5, suppZ6ment au nOIO, Tome 4 2 , octobre 1981 page C5-61
a AND 6 PEAKS OF COLD WORKED AND HYDROGEN CHARGED MOLYBDENUM
N . I g a t a , K. Miyahara, K. Hakomori, T . Miyagi and H. yoshidaX
Department o f Materials Science, University o f Tokyo, Bunkyo-ku, Tokyo 113, Japan
"Kyoto University Reactor
A b s t r a c t . - I n t e r n a l f r i c t i o n o f c o l d worked and h y d r o g e n c h a r g e d molybdenum w a s m e a s u r e d f r o m 90 t o 400K a t a b o u t 800Hz. A f t e r c o l d work o n l y t h e a p e a k was o b s e r v e d a t 120K. When h y d r o g e n was c h a r g e d , t h e peak was o b s e r v e d a t a b o u t 380
-
400K i n t h e f i r s t r u n , b u t i n t h e s e c o n d r u n t h i s p e a k s h i f t e d t o l o w e r t e m p e r a t u r e a r o u n d 300K. T h e a p e a k was s u p p r e s s e d and t h e B p e a k showed a maximum when h y d r o g e n c h a r g i n g t i m e i n c r e a s e d . T h e s e b e h a v i o r s w e r e i n t e r p r e t e d by I g a t a ' s m o d e l .1. I n t r o d u c t i o n . - Molybdenum i s c o n s i d e r e d t o b e a u s e f u l c a n d i d a t e b a s e m e t a l f o r n u c l e a r f u s i o n m a t e r i a l s . F u n d a m e n t a l s t u d y o n i n t e r - n a l f r i c t i o n o f molybdenum i s n o t o n l y i m p o r t a n t f o r c l a r i f y i n g t h e b e h a v i o r o f c r y s t a l l i n e l a t t i c e d e f e c t s i n BCC m e t a l s , b u t a l s o v e r y u s e f u l f o r t h e c h a r a c t e r i z a t i o n o f n u c l e a r f u s i o n m a t e r i a l s , f o r exam- p l e s , l i m i t t e r o r t h e f i r s t w a l l m a t e r i a l . H i t h e r t o t h e d a t a on
i n t e r n a l f r i c t i o n o f molybdenum i s f e w ( ' ' , and a s f o r c o l d worked and h y d r o g e n c h a r g e d molybdenum t h e r e i s o n l y o n e p a p e r ( 2 ) . I n t h i s i n v e s t i g a t i o n , t h e o b j e c t i v e i s t o i n v e s t i g a t e t h e r e l a x a t i o n s p e c t r a of c o l d worked and h y d r o g e n c h a r g e d molybdenum and t o c l a r i f y t h e be- h a v i o r s of d i s l o c a t i o n s and h y d r o g e n a t o m s .
2 . E x p e r i m e n t a l P r o c e d u r e . - The m a t e r i a l u s e d i s molybdenum w h i c h was made by Tokyo S h i b a u r a E l e c t r i c Co. The s p e c i m e n s i z e s were l m m x
7
-
9mm x 100-
120mm. T h o s e s p e c i m e n s w e r e a n n e a l e d a t 1,700K f o r 1 . 5 h r i n vacuum o f 5 x t o r r . Then t h o s e w e r e c o l d worked by I n s t r o n t y p e t e n s i l e t e s t i n g m a c h i n e t o 4.2-
4 . 8 % . S t r a i n r a t e was 1 x s-I. Hydrogen was c h a r g e d by a c a t h o d e e l e c t r o l y t i c m e t h o d . The c h a r g i n g c o n d i t i o n s a r e a s f o l l o w s :E l e c t r o l y t i c s o l u t i o n 3 . 3 N H2S04 s o l u t i o n
Anode p l a t i n u m p l a t e
E l e c t r i c c u r r e n t d e n s i t y 50mA/cm 2
Hydrogen c h a r g e was c o n t r o l l e d t h r o u g h c h a r g i n g t i m e 5 h r , 1 5 h r , 1 8 . 5 h r and 3 0 h r . I n t e r n a l f r i c t i o n was m e a s u r e d w i t h t h e t r a n s v e r s e v i b r a t i o n m e t h o d , i n b o t h vacuum o r a i r .
Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1981508
65-62 JOURNAL DE PHYSIQUE
3. E x p e r i m e n t a l R e s u l t s . - A f t e r a n n e a l i n g a t 1 , 7 0 0 K f o r 5.4 x
l o 3
s , t h e r e i s n o p e a k a s shown i n F i g . 1 a n d t h e b a c k g r o u n d w a s a s low a s Then a f t e r t h e same a n n e a l i n g p r o c e s s , h y d r o g e n w a s c h a r g e d f o r 5.4 xl o 4
s a t t h e c u r r e n t o f 5.0 x 1 0 ' ~ m - ~ . T h e f i r s t r u n w a s d o n e i n a i r f r o m 95K-
420K a n d t h e s e c o n d r u n w a s t h e same, t h e r e w e r e n o p e a k s i n b o t h c a s e s a n d t h e b a c k g r o u n d w a s a l i t t l e h i g h e r t h a n t h e a n n e a l e d s t a t e . A f t e r t e n s i l e c o l d work t o 4 . 3 % , t h e r e s u l t s f o r t h e f i r s t r u n a n d t h e s e c o n d r u n i n a i r a r e shown i n F i g . 2 . One p e a k w a s c o b s e r v e d a t a b o u t 130K. T h i s p e a k seemed t o b e a p e a k w h i c h w a s f o u n d b y Chambers e t a l . I n t h e s e c o n d r u n t h e p e a k w a s a l i t t l e l o w e r t h a n t h a t i n t h e f i r s t r u n . When t h e same s p e c i m e n w a s m e a s u r e d i n vacuum, o n l y t h e b a c k g r o u n d w a s l o w e r .100 200 300 400 100 200 300 LOO
Temperature ( K ) Temperature ( K )
F i g . 1 I n t e r n a l f r i c t i o n o f F i g . 2 I n t e r n a l f r i c t i o n of molybdenum a n e a l e d a t 1 , 7 0 0 K molybdenum 4.2 % d e f o r m e d a t f o r 5.4 x
l o 9
s a n d m e a s u r e d i n 300K a n d m e a s u r e d i n a i r . vacuum.I n t h e n e x t , when h y d r o g e n was c h a r g e d t o t h e c o l d w o r k e d s p e c i - men o n e m o r e p e a k e x c e p t t h e a p e a k w a s o b s e r v e d . T h e r e s u l t i s shown
i n F i g . 3 ( a ) a n d ( b )
.
A s shown i n t h e s e f i g u r e s , t w o p e a k s were ob- s e r v e d a t 135K a n d 380K-
400K i n a i r . The l a t t e r p e a k seems t o b eB
p e a k p r e v i o u s l y f o u n d by C h a m b e r s e t a l . ( l ) I n t h e s e c o n d r u n t h e p e a k s h i f t e d t o lower t e m p e r a t u r e a r o u n d 300K-
32UK, w h i c h w e d e s i g - n a t e d a s f$' p e a k . The6'
p e a k h e i g h t i n c r e a s e d i n t h e s e c o n d r u n c o m p a r e d w i t h t h e f.! p e a k o b s e r v e d i n t h e f i r s t r u n . I n t h e t h i r d r u n t h i s p e a k r e m a i n e d a n d f.! p e a k w a s n o t o b s e r v e d . T h e s i m i l a r b e h a v i o r were o b s e r v e d i n vacuum. T h e r e s u l t i s shown i n F i g . 4. T h e a p e a k w a s s u p p r e s s e d b y h y d r o g e n c h a r g i n g i n b o t h a i r a n d vacuum. T h eB
o r 8 ' p e a k became s m a l l e r i n vacuum compared w i t h t h e r e s u l t s i n a i r p o s - s i b l y b e c a u s e vacuum e n h a n c e t h e e s c a p e o f h y d r o g e n f r o m t h e s p e c i m e n .01 , . . . I
103 200 300 LOO
Temperature ( K )
F a . 3 ( a ) I n t e r n a l f r i c t i o n of molybdenum, 4.3% deformed a t 300K,4hydrogenated 5 0 r - ~ 1.8
x
1 0 s a t 5.0 x 1 0 Am and measured i n a i r .0 I1 0 n . iW 8 . 3 0 . 403 1
Temperature ( K )
F i g . 3 ( b ) I n t e r n a l f r i c t i o n of molybdenum, 4.2% deformed a t 300K,4hydrogenated 5 0 r - ~ 6.7 x 10 s a t 5.0 x 10 Am and measured i n a i r .
F i g . 4 I n t e r n a l f r i c t i o n of molybdenum,,4.3% deformed
a t 300K,4hydrogenated 5 0 r - ~ 1 . 8 x 10 s a t 5.0 x 1 0 Am and measured i n vacuum.
~ l ' . ' . . . '
100 200 300 AM)
Temperature ( K 1
When t h e c o l d worked and hydrogen c h a r g e d s p e c i m e n s w e r e meas- u r e d i n vacuum, t h e a peak became h i g h e r and t h e 6 peak o r t h e 6 ' peak became s m a l l e r p o s s i b l y b e c a u s e hydrogen d i f f u s e d o u t from t h e s p e c i - men. When t h e hydrogen was c h a r g e d f o r l o n g e r t i m e , t h e a peak was
s u p p r e s s e d and t h e B peak o r t h e B ' peak became h i g h e r . F i g . 5 and F i g . 6 show t h e c h a n g e of a peak and B peak measured i n a i r a s t h e f u n c t i o n of hydrogen c h a r g i n g t i m e a f t e r c o l d work. The peak h e i g h t s i n t h o s e f i g u r e s w e r e t a k e n assuming t h a t t h e minimum v a l u e was back- ground damping. The a peak h e i g h t d e c r e a s e d w i t h t h e hydrogen
c h a r g i n g t i m e , and when measured i n vacuum t h e c h a n g e was l e s s com- p a r e d w i t h d a t a t a k e n i n a i r . The 6 peak h e i g h t i n c r e a s e d w i t h hydrogen c h a r g e and t h e r e was maximum a t a c e r t a i n hydrogen c h a r g i n g t i m e . The peak t e m p e r a t u r e of t h e a peak d e c r e a s e d w i t h t h e hydrogen
C5-64 JOURNAL DE PHYSIQUE
c h a r g i n g t i m e i n b o t h a i r a n d vacuum. T h e c h a n g e was l e s s i n vacuum t h a n i n
a i r .
T h e p e a k t e m p e r a t u r e o f t h e f? a n d f ? ' p e a k d i d n o t c h a n g e s o much w i t h t h e h y d r o g e n c h a r g i n g t i m e i n e i t h e r a i r a n d vacuum.oL0 2 1 6 8 10 I
Hydrogen Charg~rq ~drne(xl@s) 0'0 riydrcgen Charging itme(xl@s)
i i i
8 10'
F i g . 5 R e l a t i o n b e t w e e n a F i g . 6 R e l a t i o n b e t w e e n B p e a k h e i g h t a n d H c h a r g i n g p e a k h e i g h t a n d H c h a r g i n g t i m e , m e a s u r e d i n a i r . t i m e , m e a s u r e d i n a i r . 4. D i s c u s s i o n s
4 . 1 T h e a c t i v a t i o n e n e r g y a n d t h e f r e q u e n c y f a c t o r . - The a p e a k and t h e f? p e a k r e c i p r o c a l p e a k t e m p e r a t u r e s a r e p l o t t e d w i t h m e a s u r i n g f r e q u e n c y i n F i g . 7. T h e a p e a k t e m p e r a t u r e i n o u r e x p e r i m e n t was a l i t t l e h i g h e r t h a n t h e p r e v i o u s l y r e p o r t e d d a t a . B u t i f t h o s e d a t a a r e c o m b i n e d w i t h F o u q u e t ' s d a t a ( 6 ) t h e a c t i v a t i o n e n e r g y was 0.18eV and t h e f r e q u e n c y f a c t o r was 1 0 ~ ~ ' ~ . T h e a c t i v a t i o n e n e r g y o f t h e f3
1 0 . 5 p e a k w a s 0.46eV a n d t h e f r e q u e n c y f a c t o r was 1 0
.
F i g . 7 A r r h e n i u s p l o t o f p e a k a n d B p e a k
m P r e s e n t work
4 - 2 % d e f o r m e d ( 1 9 8 1 ) o Chamber e t a l : s r e s u l t ( 3 )
5 . 0 % d e f o r m e d ( 1 9 6 2 ) F o u q u e t e t
ails
r e s u l t ( 4 )5 . 0 % d e f o r m e d ( 1 9 7 0 ) G i b a l a e t a l : s r e s u l t ( 5 )
3 0 % d e f o r m e d ( 1 9 7 3 )
4.2 E f f e c t o f c o l d work and h y d r o g e n . - The a p e a k a p p e a r s o n l y i n c o l d worked s p e c i m e n s , and e v e n i n z o n e - r e f i n e d molybdenum ( 6 )
,
t h e a p e a k a p p e a r s a t t h e same t e m p e r a t u r e w i t h t h e l e s s p u r e s p e c i m e n u s e d i n t h i s work. S o , t h e a p e a k i s c o n s i d e r e d t o b e d u e t o i n t r i n s i c d i s - l o c a t i o n r e l a x a t i o n . A s f o r t h e i n t r i n s i c d i s l o c a t i o n r e l a x a t i o n , k i n k m i g r a t i o n a n d d o u b l e k i n k f o r m a t i o n p r o c e s s e s a r e e x p e c t e d . However, i n t h e c a s e o f k i n k m i g r a t i o n , i t i s c o n s i d e r e d t h a t t h e f r e - q u e n c y f a c t o r i s s e n s i t i v e t o t h e i m p u r i t y c o n c e n t r a t i o n ( ' ) . I n t h i s r e s u l t , s i n c e t h e f r e q u e n c y f a c t o r seems n o t t o b e d e p e n d i n g o n impu- r i t y c o n c e n t r a t i o n , t h e r e l a x a t i o n would b e a t t r i b u t e d t o t h e d o u b l e( 8 ) k i n k f o r m a t i o n mechanism
.
The a peak i s s u p p r e s s e d i n t h e c o l d worked a n d h y d r o g e n a t e d m o - lybdenum. T h i s b e h a v i o r i s s i m i l a r w i t h t h e r e s u l t s o f i r o n " ) ( I 0 )
,
( 1 3 ) b u t d i f f e r e n t f r o m t h e r e s u l t s o f niobium('') (12) and vanadium
.
T h i s s u p p r e s s i o n o f t h e a p e a k c a n b e u n d e r s t o o d by t h e model o f t h e p i n n i n g e f f e c t s o n d o u b l e k i n k f o r m a t i o n ( 1 4 ) ( 1 5 ) ( 1 6 )
W i t h i n c r e a s i n g h y d r o g e n c h a r g i n g t i m e , t h e a p e a k h e i g h t c o n - t i n u e s t o d e c r e a s e a s shown i n F i g . 5 , b u t t h e f3 p e a k h e i g h t i n c r e a s e s and t h e n d e c r e a s e s beyond t h e maximum a s shown i n F i g . 6. his phe- nomena c a n b e i n t e r p r e t e d by t h e model o f t h e c a t a s t r o f i c u n p i n n i n g i n i t i a t e d f r o m t h e r m a l u n p i n n i n g o f d o u b l e l o o p s p r o p o s e d by I g a t a e t a 1 ( I 4 ) ( I 5 ) . The r e a s o n why t h e f3 p e a k s h i f t s t o t h e l o w e r t e m p e r a t u r e a f t e r h e a t i n g t o 400K would b e t h a t t h e m i g r a t i o n o f h y d r o g e n a t o m s t o d i s l o c a t i o n s and t h e i n c r e a s e o f t h e h y d r o g e n atom c o n c e n t r a t i o n a l o n g d i s l o c a t i o n s l e a d t o t h e i n c r e a s e o f t h e f r e q u e n c y f a c t o r a t t h e t h e r m a l u n p i n n i n g o f d i s l o c a t i o n s o r t o t h e d e c r e a s e o f p i n n i n g e n e r g y
( 1 7 ) t h r o u g h t h e d e c r e a s e o f e l a s t i c m o d u l u s by h y d r o g e n a t m o s p h e r e
.
The h y d r o g e n atom would b e m o b i l e d u r i n g t h e 1st r u n , i f t h e d i f f u s i o n 1 4 7 0 0 )
c o n s t a n t i s g i v e n by D= 2 x
l o b 2
e x p (-.
E l e c t r o n m i c r o p h o t o - g r a p h y o f c o l d worked and h y d r o g e n c h a r g e d molybdenum showed t h e d i s l o c a t i o n t a n g l i n g s t r u c t u r e , and n o e v i d e n c e f o r h y d r i d e p r e c i p i - t a t e s was o b s e r v e d . T h i s shows t h e i m p o r t a n c e o f s o l u t e h y d r o g e n a t o m s .5. Summary.
(1) By c o l d w o r k i n g o f molybdenum o n l y t h e a peak was o b s e r v e d a t 130K i n t h e m e a s u r e m e n t a t 800Hz, b u t n o f3 p e a k was o b s e r v e d . ( 2 ) By h y d r o g e n c h a r g i n g t h e f3 p e a k a p p e a r e d a t a b o u t 400K, a n d t h e
a p e a k was s u p p r e s s e d .
( 3 ) I n t h e s e c o n d m e a s u r e m e n t r u n a f t e r h e a t i n g t o 400K, t h e f3 peak s h i f t e d t o l o w e r t e m p e r a t u r e , w h i c h was d e s i g n a t e d a s t h e B ' p e a k , b u t t h e a p e a k l i t t l e s h i f t e d .
C5-66 JOURNAL DE PHYSIQUE
( 4 ) The a b o v e b e h a v i o r s i n molybdenum a r e v e r y s i m i l a r w i t h t h e r e s u l t s o f h y d r o g e n a t e d i r o n , and d i f f e r e n t f r o m t h e r e s u l t s o f h y d r o g e n a t e d n i o b i u m o r v a n a d i u m .
( 5 ) The a p e a k o n l y d e c r e a s e d w i t h h y d r o g e n c h a r g i n g b u t t h e f3 p e a k showed t h e maximum v e r s u s h y d r o g e n c h a r g i n g t i m e .
( 6 ) The b e h a v i o r o f t h e f3 p e a k was i n t e r p r e t e d by I g a t a ' s m o d e l . REFERENCES
(1) R. Chambers; P h y s i c a l A c o u s t i c s Vol.3A ( e d i t e d by W.P. Mason 1 9 6 6 , Academic P r e s s ) , p . 1 2 3 .
( 2 ) YE.S. Kodes e t a l . ; F i z . m e t a l m e t a l l o v e d .
2
( 1 9 7 2 1 , 431.( 3 ) R . Chambers e t a l . ; A c t a M e t .
10
( 1 9 6 2 ) , 466.( 4 ) J. d e F o u q u e t e t a l . ; J . P h y s . Chem. S o l i d s
31
( 1 9 7 0 ),
1 9 0 1 . ( 5 ) R. G i b a l a e t a l . ; J . P h y s . F : M e t a l P h y s ,3
( 1 9 7 3 ) , 1 7 8 9 .( 6 ) J . N . Lomer and C.R.A. S u t t o n ; P r o c . 3 r d E u r o p . C o n f . o n " I n t e r n a l F r i c t i o n a n d u l t r a s o n i c A t t e n u a t i o n i n S o l i d s " ( M a n c h e s t e r , J u l y
1 9 8 0 ) , p . 1 9 9 .
( 7 ) C. ~ G t h r i c h ; S c r i p t a M e t . ,
2
( 1 9 7 5 ) , 641.( 8 ) A . S e e g e r ; P h i l . Mag.,
1
( 1 9 5 6 ) , 651.( 9 ) P. M o s e r , J . F . D u f r e s n e a n d I . G . R i t c h i e ; P r o c . ICIFUAS-6 ( J u l y , 1 9 7 7 , Tokyo, J a p a n ) , p. 473.
( 1 0 ) K . S a k a m o t o and M. S h i m a d a ; i b i d . , p . 683.
(11) F.M. M a z z o l a i a n d M. Nuovo; S o l i d S t a t e Comm.,
2
( 1 9 6 9 ) , 1 0 3 . ( 1 2 ) N. I g a t a , H . Murakami and K . Kuramochi; S c r i p t a M e t . ,13
( 1 9 7 9 ) ,1.0 3
.
( 1 3 ) K . S h i b a t a , M . Koiwa and 0. ~ o s h i n a r i ; T r a n s . J a p a n . I n s t . M e t a l s 1 9 ( 1 9 7 8 ) , 491.
-
( 1 4 ) N. I g a t a , F. W a t a r i , K . M i y a h a r a , S. S a t o and H . Y o s h i d a : C r y s t a l L a t t i c e D e f e c t s
5
( 1 9 7 5 ) , 95.( 1 5 ) N. I g a t a , F. W a t a r i , A. Yamaguchi, K . M i y a h a r a and S. S a t o ;
P r o c . 5 t h I n t . C o n f . I n t e r n a l F r i c t i o n and U l t r a s o n i c A t t e n u a t i o n i n C r y s t a l l i n e S o l i d s , V o l . 1 1 ( 1 9 7 5 ) , 297.
( 1 6 ) N . I g a t a , A. Kohyama, K . M i y a h a r a , S . S a t o and H. Y o s h i d a ; M e c h a n i c a l B e h a v i o r o f M a t e r i a l s , V o l . 1 (The S o c i e t y o f M a t e r i a l s S c i e n c e , J a p a n , 1 9 7 2 ) , 58.
( 1 7 ) H . K . B i r n b a u m ; P r o c . o f ICIFUAS-6 (Tokyo, J u l y , 1 9 7 7 ) , p . 73.
( 1 8 ) H.L. H i l l ; J . M e t a l s ,
