Effects of Aging Treatment on the Microstructure and ...
13
時效熱處理對鐵-15 錳-10 鋁-1 碳合金 顯微結構與機械性質影響之研究 Effects of Aging Treatment on the Microstructure and Mechanical Property of the Fe-15Mn-10Al-1C Alloy 吳忠春 *1 楊政峰 1 張維揚 1 陳韋志 2 Chung-Chun Wu, Cheng-Feng Yang, Wei-Yang Chang, Wei-Chih Chen 1. 南台科技大學機械工程研究所 2. 南台科技大學機電科技研究所 電話:06-2427001 E-mail:[email protected] 摘要 Fe-15Mn-10Al-1C 合金在固溶狀態下之 顯微結構組織為肥粒體和沃斯田體雙相結構， D03 規律相會以 αB2α+D0 3 連續規律相變 化的機構在肥粒體基地內形成，且在沃斯田體 基地內亦可觀察到(Fe,Mn)3AlCx 碳化物的析 出，顯示鋁元素含量的提高不僅會形成(α+γ) 雙相組織，亦會促使 D0 3 規律相與 κ 相碳化物 的形成。本合金經 650℃時效處理後，發現在 晶粒邊界上可觀察到 γκ´+B2 的相分解反應， 與以前學者觀察到的 γα+κ´ 、 γκ´+β-Mn 及 γκ´+D0 3 均明顯不同。此外 B2α+D0 3 規律 相轉換溫度提高至 575℃~600℃之間，此結果 與過去學者在鐵錳鋁碳合金相變化所觀察到 的 α+B2α+D0 3 規律化相變態不同。本論文 合金表面硬度明顯比 Fe-15Mn-8Al-1C 合金還 要高出許多，其最主要原因除了形成肥粒體和 沃斯田體的雙相組織之外，在固溶狀態下即有 大量 κ 相碳化物在沃斯田體基地內形成，使得 合金表面硬度值大幅上升。 關鍵字：鐵錳鋁碳合金、B2 及 D0 3 規律相、 (Fe,Mn) 3 AlCx 碳化物、相分解反應 Abstract In the as-quenched condition, the microstructure of the Fe-15Mn-10Al-1C alloy was the mixture of ferrite and austenite phases. TEM examinations revealed that (Fe,Mn) 3 AlCx carbides precipitated within the austenite matrix , and (B2+D0 3 ) ordered phases could be found within the ferrite region by the mechanism of α→α+B2→α+D0 3 ordering transition. This result indicated that the increase of Al addition in the Fe-Mn-Al-c alloy would enhance both the formation of ordered phases with the ferrite matrix and precipitation of κ-carbides within the austenite matrix. When the Fe-15Mn-10Al-1C alloy was aged at 650℃ for 24 hours, phase decompositi- on of γ→κ´+B2 could be observed on the auste- nite grain boundary. It is worthwhile to note that the γ→κ´+B2 transformation was quite different from γ→α+κ´, γ→κ´+D0 3 and γ→κ´+β-Mn by other workers. The transition temperature of B2→α+D0 3 ordered transformation was found to be within the narrow range of 575℃ and 600℃, which was also quite different from the α+B2→α+D0 3 transition observed in the Fe-Mn-Al-C alloy before by other researchers.
Transcript of Effects of Aging Treatment on the Microstructure and ...
SKD11Property of the Fe-15Mn-10Al-1C Alloy
*1 1 1 2
Chung-Chun Wu, Cheng-Feng Yang, Wei-Yang Chang, Wei-Chih Chen
1.
2.
:06-2427001 E-mail:[email protected]
(Fe,Mn)3AlCx
γα+κ γκ´+β-Mn
γκ´+D03 B2α+D03
575~600
Fe-15Mn-8Al-1C
(Fe,Mn)3AlCx
was the mixture of ferrite and austenite phases.
TEM examinations revealed that (Fe,Mn)3AlCx
carbides precipitated within the austenite matrix ,
and (B2+D03) ordered phases could be found
within the ferrite region by the mechanism of
α→α+B2→α+D03 ordering transition. This
result indicated that the increase of Al addition
in the Fe-Mn-Al-c alloy would enhance both the
formation of ordered phases with the ferrite
matrix and precipitation of κ-carbides within the
austenite matrix.
aged at 650 for 24 hours, phase decompositi-
on of γ→κ´+B2 could be observed on the auste-
nite grain boundary. It is worthwhile to note that
the γ→κ´+B2 transformation was quite different
from γ→α+κ´, γ→κ´+D03 and γ→κ´+β-Mn by
other workers.
the narrow range of 575 and 600, which
was also quite different from the α+B2→α+D03
transition observed in the Fe-Mn-Al-C alloy
before by other researchers.
Compared with Fe-15Mn-8Al-1C alloy ,
surface hardness property. In addition to the
mixture of ferrite and austenite phases, the main
reason may be both the formation of ordered
phases within the ferrite region and the
precipitation of (Fe,Mn)3AlCx carbides
the rapidly quenching process.
KeywordFe-Mn-Al-C alloy, dual-phase
phases, (Fe,Mn)3AlCx carbides,
Fe-15Mn-10Al-1C
80A/cm 2 ~120A/cm
(holder)
X
1050
(twin)
XRD
Fe-15Mn-10Al-1C
BCC FCC
condition. (F: ferrite matrix; A: austenite matrix)
Fig.2 XRD patterns of the Fe-15Mn-10Al-1C
alloy in the as-quenched condition.
23.8 °30.8° 34.1°
JCPDS 65-0543
(Fe,Mn)3AlCx (κ ) 2θ 23.8°
34.1° (100) (110)
3.7Å 2θ 30.8°
B2 D03d
B2(100) D03 (200)
B2 D03
TEM 3
(a)(b) Fe-15Mn-8Al-1C 1050
as-quenched condition.(a) and (b) show [100]
and [011] SADPs of the ferrite region.
[001]
-10Al -1C alloy in the as-quenched condition ;(a)
(200) D03 DF electron micrograph taken from
the ferrite region; (b) (200) D03 DF micrograph at
larger magnification.
D03 D03
10nm
α+ D0 3
α → α + B2 → α + D03
Fe-15Mn-10Al-1C alloy in the as-quenched
condition, taken from the same ferrite region
as Fig. 4(a) and 4(b)
1050
1050
50 nm
Fe-15Mn-8Al-1C alloy in the as-quenched
condition. (a) The zone axes were (a) [001] and
[011] directions, respectively.(hkl: anstenite ; hkl:
κ- carbide)
72 XRD
XRD
Fig.7 TEM electron micrographs taken from the
austenite matrix of the Fe-15Mn -8Al-1C alloy
in the as-quenched condition. (a) BF
micrograph; (b) DF micrograph
D03 (111)
450 72 2θ 26.7°
D03
CC FCC
B2D03(Fe,Mn)3AlCx
D03
alloy aged at 450 for 72 hours.
TEM
450 24
(α+ D03)
450 24
κ ()
Fig.9. TEM electron micrographs of the Fe-15Mn-10
Al-1C alloy aged at 450 for 24 hours. (a)
SADP taken from the ferrite region, the zone
axis is [011] direction. (b) (200) D03 DF
micrograph; (c) (111) D03 DF micrograph.
Fig10. TEM electron micrographs of the
Fe-15Mn-10Al-1C alloy aged at 450 for 24
hours. (a) BF electron micrographs taken from
the austenite matrix (b)(100) κ-carbide DF
electron micrograph taken from austenite matrix.
,
FCC B2D03
(Fe,Mn)3AlCx (κ)
450 κ
20nm , 450
,
(b)(200) D03
(α+ D03)
24 TEM
D03 B2
Fe-15Mn -10Al-1C 550
24 (α + D03)
B2
24
κ , 550
,κ
,
→ κ + α
Fe-15Mn-10Al-1C alloy aged at 550 for 24
hours, (a)(200) D03 DF electron micrographs
taken from ferrite region(b) (100) D03 DF
micrograph taken from the same region as
Fig.11(a)
600 24
(111) D03
(200) D03 B2
24 hours.(a) (111) D03 DF taken from
ferrite region(b) (200) D03 DF taken from
the same ferrite region as Fig.12(a).
Fig13. Optical micrograph of the Fe-15Mn-10-
Al -1C alloy aged at 650 for 24 hours.
( F : ferrite matrix; A: austenite matrix)
B2
(α + D03)
575 600
550
24
B2
D03 D03
(α + B2) 15 (a) Fe-15Mn
-10Al-1C 650 24
D03
α + B2
10Al-1C alloy aged at 650 for 24 hours. (a)
and (b) show (200) D03 DF and (111)DF D03 DF
electron micrographs ,respectively.
(α + B2)
Fe-15Mn-10Al-1C alloy aged at 650 for 24
hours (a)BF electron mircograph taken from the
austenite grain boundary.(b) SADP taken from
the region near by κ -carbides. (c) (111) D03 DF
electron micrograph.
Fe-15Mn-10Al-1C
κ
450
D03
, 550 and 650 for 24 hours on the
surface hardness property of the (a)
Fe-15Mn-10Al-1C alloy, (b) Fe-15Mn-8Al
D03
(200)D03
B2D03
γ→κ´+D03
1. X. J. Liu, S. M. Hao, L. Y. Xu. Y. F. Guo
and H. Chen: “Experimental Study of the
Phase Equilibria in the Fe-Mn-Al
System.”, Metal. And Mater. Trans. A, vol.
27A, 1996, pp. 2429-2435.
2. M. B. Kannan, R. K. S. Raman and S.
Khoddam: “Comparative studies on the
corrosion properties of a Fe–Mn–Al–C
steel and an interstitial-free steel”,
Corrosion Science, 50 (2008) .pp. 2879–
2884.
Hardening Austenitic Alloys”, Metal
pp. 95.
of Austenitic Alloys Containing
the ASM, vol. 52, 1960, pp. 898.
5. S. K. Banerji: “An Austenitic Stainless
Steel Without Nickel and Chromium”,
Metal Progress, April, 1978, pp. 59
6. J. S. Dunning, M. L. Glenn, and H. W.
Leavenworth, Jr.: “Substitutes for
7. 1997
21-29
8. C. N. Hwang, C. Y. Chan and T. F. Liu:
“Grain BoundaryPrecipitation in an
1993,pp.263-268.
9. T. F. Liu, G. C. Uen, C. Y. Chao, Y. L. Lin
and C. C. Wu: “Phase Transformation in
an Fe-9.0Al-29.5Mn-1.2Si Alloy”, Metall.
10. A. Inoue, T. Minemure, A. Kitamura and T.
Masumoto, Metall . Trans. A, Vo l. 12A,
June. , 1981, pp.1041-1046.
Science and Engineering, A1 36,1991 ,pp.
141 -149.
of phase transformations within the
miscibility gap of Fe-Rich Fe-Al alloys”,
Acta Metall., vol. 24, 1976, pp. 425-437.
13. 2004-9 -30 -1 -12
J. Geenen, M. Kreuss: ”Investigations on
phase transformations and B2- D03
superlattices in ordered iron aluminium
alloys by fim-atom probe and TEM”,
Scripta Metall. Vol 24, 1990, pp. 51-56.
16. 2009 -15 -8
-1
*1 1 1 2
Chung-Chun Wu, Cheng-Feng Yang, Wei-Yang Chang, Wei-Chih Chen
1.
2.
:06-2427001 E-mail:[email protected]
(Fe,Mn)3AlCx
γα+κ γκ´+β-Mn
γκ´+D03 B2α+D03
575~600
Fe-15Mn-8Al-1C
(Fe,Mn)3AlCx
was the mixture of ferrite and austenite phases.
TEM examinations revealed that (Fe,Mn)3AlCx
carbides precipitated within the austenite matrix ,
and (B2+D03) ordered phases could be found
within the ferrite region by the mechanism of
α→α+B2→α+D03 ordering transition. This
result indicated that the increase of Al addition
in the Fe-Mn-Al-c alloy would enhance both the
formation of ordered phases with the ferrite
matrix and precipitation of κ-carbides within the
austenite matrix.
aged at 650 for 24 hours, phase decompositi-
on of γ→κ´+B2 could be observed on the auste-
nite grain boundary. It is worthwhile to note that
the γ→κ´+B2 transformation was quite different
from γ→α+κ´, γ→κ´+D03 and γ→κ´+β-Mn by
other workers.
the narrow range of 575 and 600, which
was also quite different from the α+B2→α+D03
transition observed in the Fe-Mn-Al-C alloy
before by other researchers.
Compared with Fe-15Mn-8Al-1C alloy ,
surface hardness property. In addition to the
mixture of ferrite and austenite phases, the main
reason may be both the formation of ordered
phases within the ferrite region and the
precipitation of (Fe,Mn)3AlCx carbides
the rapidly quenching process.
KeywordFe-Mn-Al-C alloy, dual-phase
phases, (Fe,Mn)3AlCx carbides,
Fe-15Mn-10Al-1C
80A/cm 2 ~120A/cm
(holder)
X
1050
(twin)
XRD
Fe-15Mn-10Al-1C
BCC FCC
condition. (F: ferrite matrix; A: austenite matrix)
Fig.2 XRD patterns of the Fe-15Mn-10Al-1C
alloy in the as-quenched condition.
23.8 °30.8° 34.1°
JCPDS 65-0543
(Fe,Mn)3AlCx (κ ) 2θ 23.8°
34.1° (100) (110)
3.7Å 2θ 30.8°
B2 D03d
B2(100) D03 (200)
B2 D03
TEM 3
(a)(b) Fe-15Mn-8Al-1C 1050
as-quenched condition.(a) and (b) show [100]
and [011] SADPs of the ferrite region.
[001]
-10Al -1C alloy in the as-quenched condition ;(a)
(200) D03 DF electron micrograph taken from
the ferrite region; (b) (200) D03 DF micrograph at
larger magnification.
D03 D03
10nm
α+ D0 3
α → α + B2 → α + D03
Fe-15Mn-10Al-1C alloy in the as-quenched
condition, taken from the same ferrite region
as Fig. 4(a) and 4(b)
1050
1050
50 nm
Fe-15Mn-8Al-1C alloy in the as-quenched
condition. (a) The zone axes were (a) [001] and
[011] directions, respectively.(hkl: anstenite ; hkl:
κ- carbide)
72 XRD
XRD
Fig.7 TEM electron micrographs taken from the
austenite matrix of the Fe-15Mn -8Al-1C alloy
in the as-quenched condition. (a) BF
micrograph; (b) DF micrograph
D03 (111)
450 72 2θ 26.7°
D03
CC FCC
B2D03(Fe,Mn)3AlCx
D03
alloy aged at 450 for 72 hours.
TEM
450 24
(α+ D03)
450 24
κ ()
Fig.9. TEM electron micrographs of the Fe-15Mn-10
Al-1C alloy aged at 450 for 24 hours. (a)
SADP taken from the ferrite region, the zone
axis is [011] direction. (b) (200) D03 DF
micrograph; (c) (111) D03 DF micrograph.
Fig10. TEM electron micrographs of the
Fe-15Mn-10Al-1C alloy aged at 450 for 24
hours. (a) BF electron micrographs taken from
the austenite matrix (b)(100) κ-carbide DF
electron micrograph taken from austenite matrix.
,
FCC B2D03
(Fe,Mn)3AlCx (κ)
450 κ
20nm , 450
,
(b)(200) D03
(α+ D03)
24 TEM
D03 B2
Fe-15Mn -10Al-1C 550
24 (α + D03)
B2
24
κ , 550
,κ
,
→ κ + α
Fe-15Mn-10Al-1C alloy aged at 550 for 24
hours, (a)(200) D03 DF electron micrographs
taken from ferrite region(b) (100) D03 DF
micrograph taken from the same region as
Fig.11(a)
600 24
(111) D03
(200) D03 B2
24 hours.(a) (111) D03 DF taken from
ferrite region(b) (200) D03 DF taken from
the same ferrite region as Fig.12(a).
Fig13. Optical micrograph of the Fe-15Mn-10-
Al -1C alloy aged at 650 for 24 hours.
( F : ferrite matrix; A: austenite matrix)
B2
(α + D03)
575 600
550
24
B2
D03 D03
(α + B2) 15 (a) Fe-15Mn
-10Al-1C 650 24
D03
α + B2
10Al-1C alloy aged at 650 for 24 hours. (a)
and (b) show (200) D03 DF and (111)DF D03 DF
electron micrographs ,respectively.
(α + B2)
Fe-15Mn-10Al-1C alloy aged at 650 for 24
hours (a)BF electron mircograph taken from the
austenite grain boundary.(b) SADP taken from
the region near by κ -carbides. (c) (111) D03 DF
electron micrograph.
Fe-15Mn-10Al-1C
κ
450
D03
, 550 and 650 for 24 hours on the
surface hardness property of the (a)
Fe-15Mn-10Al-1C alloy, (b) Fe-15Mn-8Al
D03
(200)D03
B2D03
γ→κ´+D03
1. X. J. Liu, S. M. Hao, L. Y. Xu. Y. F. Guo
and H. Chen: “Experimental Study of the
Phase Equilibria in the Fe-Mn-Al
System.”, Metal. And Mater. Trans. A, vol.
27A, 1996, pp. 2429-2435.
2. M. B. Kannan, R. K. S. Raman and S.
Khoddam: “Comparative studies on the
corrosion properties of a Fe–Mn–Al–C
steel and an interstitial-free steel”,
Corrosion Science, 50 (2008) .pp. 2879–
2884.
Hardening Austenitic Alloys”, Metal
pp. 95.
of Austenitic Alloys Containing
the ASM, vol. 52, 1960, pp. 898.
5. S. K. Banerji: “An Austenitic Stainless
Steel Without Nickel and Chromium”,
Metal Progress, April, 1978, pp. 59
6. J. S. Dunning, M. L. Glenn, and H. W.
Leavenworth, Jr.: “Substitutes for
7. 1997
21-29
8. C. N. Hwang, C. Y. Chan and T. F. Liu:
“Grain BoundaryPrecipitation in an
1993,pp.263-268.
9. T. F. Liu, G. C. Uen, C. Y. Chao, Y. L. Lin
and C. C. Wu: “Phase Transformation in
an Fe-9.0Al-29.5Mn-1.2Si Alloy”, Metall.
10. A. Inoue, T. Minemure, A. Kitamura and T.
Masumoto, Metall . Trans. A, Vo l. 12A,
June. , 1981, pp.1041-1046.
Science and Engineering, A1 36,1991 ,pp.
141 -149.
of phase transformations within the
miscibility gap of Fe-Rich Fe-Al alloys”,
Acta Metall., vol. 24, 1976, pp. 425-437.
13. 2004-9 -30 -1 -12
J. Geenen, M. Kreuss: ”Investigations on
phase transformations and B2- D03
superlattices in ordered iron aluminium
alloys by fim-atom probe and TEM”,
Scripta Metall. Vol 24, 1990, pp. 51-56.
16. 2009 -15 -8
-1
