effects of thermo-magnetic heat treatment on microstructure and magnetic properties...
Post on 23-Jul-2020
0 Views
Preview:
TRANSCRIPT
Effects of Thermo-magnetic Heat Treatment on Microstructure and Magnetic Properties
of Alnico 5DG Alloy
K. Nekoee, S. Heshmati Maneh, A. Ataie
Department of Metallurgy & Materials, University of Tehran, Tehran, Iran. E-mail: sheshmat@ut.ac.ir
Abstract: In this research, Alnico 5DG alloy was melt and cast in the optimum conditions and its samples were homogenised and heat treated in a magnetic field in order to obtain the required magnetic properties. Microstructure, phase composition and magnetic properties of samples were examined in every processing step. The results indicated that the properties of samples were highly influenced by processing parameters. A proper microstructure composed of α1 magnetic phase in a texture of α2 with acceptable magnetic properties was obtained by meticulous control of the processing conditions. The results also revealed that the magnetic coercivity (and remanence) of the cast samples should be increased by an appropriate heat treatment from 12 kA/m (and 0.55 T) to 41.6 kA/m (and 1.3 T), respectively.
Keywords: Magnetic materials, Directional solidification, Alnico 5DG, Phase composition.
Vol. 12, No. 1, 1383/2004 Spring & Summer
(received: 24/8/2003, received in revised form: 14/3/2004)
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
�������� ��� �� ��� �� ��������� � �� ������� ������������ ������� Alnico 5DG
��� ! �"#!��$��%�& ��#� '�$� �() *��+�,��,
����� ���� � �� ���� ������ ������ ��� ������� ����� � � ��!� �"���� ���
-�� . :#$� ���"��� ����% �% 5DG&���� '$��� �� �&!($� � )�* +," � ��� �� &���� !�" -./� ���� �% 0� �$1 � ���!��" 2�$�� 23� )�45� �6�7�8� ��$%�� �9�
�$�� #��1 � �0"�6�7�8� �� !�� ���: ��.��<��"����� �!�" &4=�� �1 �� >���?&���� �6�7�8� @��� � �0� 2�� ���: ��$0�� ���� 1 .&� 26�% 0� ��= A$!�
��$��� '$��� B�� ��$0 �= � �����* @��� 2�"�� ��% C�:� D�!�� � ��� � ���� ���� �6�7�8� 0� 0� E��!� )�45� �!�"F$� &�α1G���0 �� α2E�: �6�7�8� @��� �
2�$ 2"� D�H: .�� ��� A$!� 1��&� �+<0��$�� ��$%�� &���� ��&!($� G���� ��� �� �0� �6�7�8� � ������� ����� KA/m IJ&�KA/m K/MI6< �0� �6�7�8� ���TNN/O
&�TPJ/I�� Q$�F�� ��$.
-�,� ���"0 ��1 : 2�S ��T�� ��6�7�8� ���� ����% ����5DG�0� ?���� �.
U��� �V1�0��� D"I�!6�� � ��� �WPG3X/ 0� �YP� IOP
)&[� 2�$��J/K/IPWJ��$�� &(6� 2�$�� JP/IJ/IPWJ(
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
$�� ��$%�� �9% �"��� �� �6�7�8� �� ��... YN
3�+ 1����%0� �1�� &� ��!61 �6�7�8� �1 �% �!��� �]�^ &" E��6�7�8���� ��#1%
�$�[� � E��� �2H��8� ��_ �/�^ 0� ����� �6�7`������% �� +� �1 ��$� �/�^ ��!61.FS 1 �% #$� a��b�� �6�7�8� ���� )2(" (�X!"� ����� � ����U�� �c�"�
����� 2c�/ .&��� ��3� �d�/�]��c"�� ���� �G'"�� ����% �1 �% McCurrie�&��72"� ��� ���� E�� ]I[.?���� �NW%�#1%PO%� E��� IJ%�%`����� �% �Alni #���
'"�� &� ��� ��� #$� 0� �% Mishima #$� ��T� 2��1� &� &S�� � &� ��� &!�"&� �1 �% ����� &c"�� ��$� �����1�f< �� ��% @��� � ?���� ��0 ���� ]J�P[.����%N?���� � W%�`������%IM%�E���JM%�2H�P%� +�&�[� � #1% � ���
D�c� �6�7�8� G����� PKJ/m MMgMOV!6�� ��: '"��� �� �� &!�".+," &���h����% @��� ��H�� �c�"� d[�[3� ������<2�S ��T�� d�4�^ � ����$�� �7�8� `T�� �%
2�� ]I[.�#��i�1� �% �/�^ �$" ��9j��&4�S 0� Nb �B�Hf��6�7�8� @��� �� �% �% ���N�"��� 2"� ���]M�k[.�1��4� l� ����%N�6�7�8� @��� �&���� ����
���� ��� ���]W[.����% �% ��$0 �$�[� &�m" &��$� &� &S���N� ��$�!�� B$�/ �� n�]� 2�S
������0" ���� ���$���#$� �� �o ����Q1�f< ����% �% 5DG ��&���� '$��� ��&��� ���� �% &� �4H: G[� �� ]Y[&��� �$�� +," �l$ ��p= ������� �6�7�8�
�� �1��� .�&���� �� 0� &4=�� �1 ��9j�Q$�� @��� � �0� ?���� ��!�"F$� �� �6�7�8�&���� 12"� ��� ��$0��.
4��' �5 ����% �% �6�7�8� @��� &��$� &� �h�N3� d�� &� 2�]�� ��9j���� ���: �o ����
��� ��#$� G��� ���� 0� �% G��X!"� q� ��.����V���$� ���F�� �V���$���� 0� D�]3� 2���Elchem ��� ��^ � KP%�� ��X!"� .��� �� �0" �%U� 2�� `T�� #�� ����
2h�3�����% Q$6�� 0� �% "� �� �% 0 Q�� 0� ��� ��X! .)�* 0� +<� �% ��l$?:&���!"� E�� ��&"� ���� &� G3X/ l$ ���U���� ��" ���: �6� &!($� �2��� �� �� .d�bFSr��&!($� � )�* �� ���� s�t�� u.H: �� 2"� �]Y[.����G&!($� ��� ��
23���$�� ��$%�� ������ &� 2�� ���: ����=�7 ���%E�� �� I2"� ��� ���� ��� .��$�� ��$%�� ����� 0� U&� ��X!"� �� �% 0 Q�� &� F�T� ����.
c5�G&���� �!�" F$� 1����!�� v��"����� � ���� v��"����� �g�����(SEM) D��Cambridge 3602�� d��/ .&���� �$���� F��% 0� ��X!"� � 1
���!�� v��"������g�����(SEM-EDX) `T�� �&���� E��� D�43� � 1���� ���= .
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
�!��= ��b��� �$5^ �Q�� YK
&���� �0� ?���� 1���< A�" r��< l$ � (XRD) X +,�4�� 2��� @��� � #��c� �6�7�8� ��% ��!"� 0� ��X!"� �Yew BC Hystersies Loop Tracer-3257 ���1�f< � ��� � �����0���� �� ��� .
6 �7����������=�7 ��E��" �$�� ��$%�� �.M:�$�� ��$%�� �����p=�6�7�8� �����.
����� � 89� E��J!($� G���� ���� v��"����� �$�]� & ������� ��� �� �1� .r�� B5[� �"���
c5: ��7G&!($� �� 2�S ��T�� 0� ��= ��� �% ���&� 2"�2�S #$� � ���� C�^ JN��!��4��&!��� &����2"� .c5�G&���� ���� �!� B5[� F����� ��1�U&��� ��p= �1
0� #�< u!H6� ���!"α)����F��� ?c�� ���4� �!�" � 2$��bcc (2"� ��p= 0� ��9� �0� � �6�7�8�� V=�F�γ)����F��� -�5" � ?c�� ���4� �!�" � 2��!"�fcc (� �� �$�]
��� ��1�� ���� v��"����� ��� .
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
$�� ��$%�� �9% �"��� �� �6�7�8� �� ��... Yk
6 �:&!($� &���� ���� v��"����� �!�" ��� �� )?: ��3� � �0��� B5[� ��.(
r��< ���� �"������< X���� Gm� E�� �� &� P`�^ 0� ��= �2"� ��� ���� ��� ��p=&4: 0� �1��6�7�8�γ2"��"��� A$!� &� 1<��"����� ��� �� $j�� �� ���.&!H�
��� #$� ����6�7�8� � �4/� 0� ��p= 0� ��9� (FeCo)α1��� ��1�� F�� ��� .A$!����� �$���� F��%G&� ��� &��� �SEM-EDX `T�� 2�� �$���� F��% A$!� ����1 &�
����G����% N� ������� U�!6 �����!"� �$���� ?���� D��S �� �% #$� I����% ��� ��� .��w�� &h=.� &� !($� �% �$���� ?���� ���& ����� U���3� �� uH$�[�
���� ���: 0T� ?���� .���"���Szymura &� ��� ��� �����1 �V���$� ��p= ?���� �� �%��2�S ����� &��� ?"�� ��� ��� 1����D�7 �$��� ��T�� ���]N[.
[4=G���� ���6< G!($� & ��� �� E�� �� M2"� ��� ���� ��� .���w &h=.� &�� [4= ����G� �6�7�8� ���6< ��6�7�8� � ������� ����� � l$�� ��6� &���� ���6<
?���� &� �% �6�7�8� � ��� G����� kA/m IJ�TNN/O�PkJ/m K/k2"� .@������ x�ct �6�7�8� &���0� ��= ����� ��p= `�^$�6�7�8� 0� 0� ����� ���[� ��p=
α1� &� ��� XRD2"� ���� ���% .
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
�!��= ��b��� �$5^ �Q�� YW
6 �;���< r��< ����+�$����� G!($� & ����� .)F = Al0.42Ni0.58�G = F, Kamacite (FeNi), Fe �H = G, FeNi(
<��=7($� &���� �$���� ?����&!&6$[� �� ��� �� �����!"� � ������� &���� �$���� ?���� �.
3!�%!/�>�) Fe Co Ni Al Cu Nb Si S
?�,�!���, &�[� JNgJMINgIPN/WgW/kMgJIgOI<I<
�@,?�,� Wk/NOK/JJkJ/IPPk/YkJ/J�X/ kMM/OOOP/O3�A � ���-�� MK/NIPI/JPYP/IJYY/kYY/JOkI/IIJ/OOI/O
E��M!($� G���� ���6< G[4= ��3�� & ����� .
c5: 0� &���� ��w&�1&!($� �� 0���� � ��� U� &��� �6�$ ��$%�� ��#��1 �� �0" ���°CIJNO d�� &� N/O�I�N/I�J�% ?:c!� � ��!�� ���: 2^" ��$%�� �� �$�� ������6�7�8� � ��� 2)Tempering (E�� C�5� I2��$o< `T�� ��% ��� .�Gc5
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
$�� ��$%�� �9% �"��� �� �6�7�8� �� ��... YY
&���� �!�"F$� &� 1�SEM 2�� d��/�� ��� ���0 ���8� &� �1���$%��#��1 �0"2"� &!���� ��% �� ��$0 ��9j���$�]� � &6$[� �� �� SEM!($� G���� & �����)E��
Ngx�(�� �!"�� �� 10� � ���� ��6�7�8� ����S���� ��1�� ��� .E���1 Ng)�Ngd����� ����!�� v��"����� �$�]� (SEM) &���� !($� �1& ����� ���$%�� �9�
��$�� ���� ��� �� x4!(� '$��� �1� .��w�� &h=.� &� ������$�� ��$%�� ��"� ��� ?S�� 2� 0��$� ����� �� u.H: &�$%�� D�7 �� ��$�� �� �6�7�8� �����
�&2"� ���% ��S�.���< r��< ���� F��%X#��1 G���� � ��� �0"&d��J2^" �+,"��$%�� �9�
�7�8� g�� $�)E��y(�!($� G���� � &6$[� �� �0� ?���� ���8� 0� ��= & ����� 2"� .0� E����)Y/ONiI/IAl(Jα0� ��p= ���6�7�8� γ���^ 0� �������8� #$�� .��r0���
����!�� v��"����� �$�]� ���6�7�8� 0� 0� ��9� α1��� ��1�� ��� .0� ��p= &w� �6�7�8�α1� ��� `T�� ���"��� �� SEM �XRD� ��1�� ����� �0���� ���
2"� 0� #$� �����w Q$�F�� 0� ��= �6�7�8� @�������5� ��� &� � ������� ������� � �6�7�8� ���6< ��6�7�8�G� �6�7�8� � ��� &0� ?���� kA/m IJ�TNN/O�
PkJ/m K/k!($� G���� �� & ��� ��&�kA/mPK �Tk/I�PkJ/m M/JO���� �� G��$� �� ��"�)E��z.(&���� �6�7�8� � ������� ����� � �6�7�8� ���6<m� ?���� &� WI%�
kJ %�[�$� �{�!� ���� ������� &���� .
)C) (E�,(
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
�!��= ��b��� �$5^ �Q�� IOO
)F) (G(6 �H�� �$�]� v��"����&$��9 ����� ����!�) .x�(!($� G����& ����� ) .)(���� G#��1
d�� &� ���J+," � 2^" �$�� ��$%�� ����6�7�8� ����� ) .v(&��� ))(&>��$%�� �� �� 2� °CKNO d�� &� K2^" �� `T�� �% ��� ) .d(&��� )v(&>��$%����2� `����°CNKO d�� &� IO"2^2"� ��� `T�� �% ��� �� .
6 �I���< r��< ����X#��1 G���� d�� &� ��� J+," � 2^" �� ��$�� ��$%�� ����� �6�7�8�.K: Al1.1Ni0.9, CoFe, Al0.42Nio.58 L: K, Kamacite (FeNi), Fe; M: L, FeNi;
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
$�� ��$%�� �9% �"��� �� �6�7�8� �� ��... IOI
6 �J� ���6< G[4= ��3�� d�� &� ��� #��1 G���J+," � 2^" �� ��$�� ��$%�� ����� �6�7�8�.
�����6�7�8� @��� �o � �0� ?���� ��<��"����� �!�" ��H�� ��1�!���< ��9j� !�� ���: �"��� ���� ��$���2^�" Q[� ��% ��� 0� &� ��"$Q+<0���$%��
#��1 |��4� �0" ��� ��2"� �.A$!��� ��� ���� ��" 2^�" Q1� � &� �1� +< 0�4=��G#��1 ��"� �0" 0� ��(FeCo)α1�&�� E���� ���� E������)E��Wgx�.(�`T���� ��$�� ��$%������� 7�8� ��6)E�� CH7I(���"� ������ α12�S ��
�3�S��>IOO<��� ����� }�!�� E]� � ��� ���� #�$< E�� &� ���)E��Wg).(�$�]�SEME�� �� &6$[� 2�S ������� G���� Wgv&� ��$0 21H� &� 2"� ��� ����%
���� C�[3� #$� �� ��� &��� G���� �!�"F$�.���< r��< ����XG���� m� +�7�8� 0� E���� &� (FeCo)α10� ����1 &� �� α2
�� ��b� E�� �� �$��~2"� ��� ���� ��� .G���� �6�7�8� @��� m� � &6$[� �� D��S �� ������� G���� �6�7�8� @���J�� ����% ��.��w�� &h=.� &� �4� ���G@���
&���� &� 2H6� �6�7�8� &!�$ ������w Q$�F�� �4H: �1 G���� � &6$[� �� �� ����������0��� �6�7�8� � ������� ����� ��! ���������� &� �� �% 24^ ���[� ��p= �����
0� ���γr��< �� &� ��� ���<2"� ��� �b"�� V1 +�$� .[4=G���� ���6< G��� &��� �� E�� �� &���� '$��� I�2"� ��� ����% .
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
�!��= ��b��� �$5^ �Q�� IOJ
)C()E�,(
)G(6 �Kv��"����� �$�]��&$��9 ����� ����!�) .x� (#��1 G���� �� ��� �0"°CIJNO &� d��J2^" +<�" 0� Q$�`��% ) .)(���� &��� G)x� (��� �$�� ��$%���6�7�8� ����� .
)v(������� &����.
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
$�� ��$%�� �9% �"��� �� �6�7�8� �� ��... IOP
6 �L��� &��� &���� +�$� ���< r��< ����.N: Al1.1Ni0.9, CoFe, Al0.96Co1.06; O: N, Kamacite (FeNi), Fe; P: O, FeNi.
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
�!��= ��b��� �$5^ �Q�� IOM
6 �7M��� G���� ���6< G[4=&���� '$��� 23� ��� &.
N�,?�� +�7�8���� �10� �T$� I(CoFe)α�� G���0 Jα)Y/ONiI/IAl ( 0� ���[� E:��= � ����1
� �p� � �6�7�8�γ����% �% �� )�45� �6�7�8� @��� &� ���"� ���� N2�S � ��� ���� V���" ��1%$Q0����#��1 �0")°CIJNO (�% DH�� &� ��� ��$�� ��$%��
�6�� �6�7�8� �����2"�.
<��=:��� &��� &���� �6�7�8� @������������ G���� � &���� '$��� .
������� O,�� 3!�%! HC (kA/m) Br (T) (BH)Max ( kJ/m );
������� K/MY PJ/INN&���� G������� K/MI PJ/IJ/PW
�@��!,?��P ��c� 0� &4�"��$�� �� #��� �7(� ����� ������ ��1�f< `�!3� 2�-�7 #$� ������: CH7
��1�f< ����PkJ/I/KIN #!��o ��!�� �� �7(� ���� � � ��!� �"���� ��� ��� ������: � ���� �1��$�0% d�F��T� ���.
Q=,� [1] Mc Curri R.A., “Ferromagnetic Materials: A Handbook on the properties of magnetically ordered substances”, Vol. 3, ed. Ep. Wohlfarth, North – Holland, Amsterdam (1982) pp. 111-184. [2] Devos K.J., “Alnico Permanent Magnet Alloys, in Magnetism and Metallurgy”, Vol. 1, Academic Press, New York, London (1969) PP. 473-512.[3] Graham Jr C.D., “Textured Magnetic Materials, in Magnetism and Metallurgy”, Vol. 2, Academic Press, New York, London (1969) pp. 723-748.
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
$�� ��$%�� �9% �"��� �� �6�7�8� �� ��... ION
[4] Pramanik S., Rao V., Monantj O.N., “Effect of niobium on the directional solidification and properties of Alnico alloys”, J. Mater. Sci. (1993) Vol. 28, pp. 1237-1244. [5] Szymura S., Golba S., “The influence of niobium on the magnetic properties of the columnar Alnico5 permanent magnets”, J. Magn. Magn. Mater. No. 24 (1981) pp. 285-287. [6] Szymura S., “The effect of boron on the magnetic properties of Alnico5 permanent magnet Alloys”, Mat. Chem. Phys. No. 13 (1985) pp. 489-495. [7] Kuznetsov V.M., “Alloying of Fe-Co-Ni-Al-Cu system (English Translation of Metallovedente in Termicheskey Obrabot ka Metallov), Vol. 29, No. 3-4 (1987) pp. 308-311. [8] Steinorth E., “Monocrystalline permanent magnets and method of making them”, U. S. Patent, No. 3085036, April (1963).
]Y[Q�� �!��= ��c" ��$��� �4c�� ���b5^ V"[���� ”���9j&!($� '$��� F$� �� �� 8� �% �!�" ����% �6�7�N&��� � 2�S �1 ���“����� #���� dm[� &^��T� �
��1� ���� ������ ����$� ��1%��_ � ��!�)IPkY(.
Dow
nloa
ded
from
ijcm
.ir a
t 19:
01 +
0430
on
Sun
day
Sep
tem
ber
20th
202
0
top related