Ag-28Cu Al5052 Ag-28Cu Al5052
Diffusion bonding of Al5052 alloy using Ag-28Cu filler metals
2005 2
Ag-28Cu Al5052
Diffusion bonding of Al5052 alloy using Ag-28Cu filler metals
2005 2


2005 2
i

Ag-28wt%Cu Al 5052
Al 5052
. Al5052
(Eutectic brazing) , (Eutectic
brazing)
,

.
1000mesh sand paper
. 500~590, 1min~60min
1Mpa, 5X10-5 torr
.
Ag-28Cu Al5052 Al-Ag-Cu 3
490 Mg, Si
. 560
2
560 .
560 580
10 80% 141Mpa
.
ii
Abstract
This study is about diffusion bonding of Al5052 alloy using Ag-28Cu insert
metal. And we investigated the brazability of Al5052 alloy with Ag-28Cu insert
metal.
Below solidus temperature of Al5052 alloy, we attempted eutectic brazing
using eutectic reaction between Al5052 alloy and Ag-28Cu insert metal. We
investigated the formation temperature of liquid phase and condition of
isothermal solidification by insert metal, also examined the microstructure and
mechanical properties of the eutectic brazed joints by various brazing condition.
The surface of the base metal to be bonded was polished with 1000mesh sand
paper, and then electropolished. And we attempted eutectic brazing under a static
pressure of 1MPa, vacuum of 5×10-5 torr and various brazing temperature(500
to 590) and time(1min to 60min).
The eutectic melting of Al5052 and Ag-28Cu insert metal occurred at about
490 that is lower than the ternary eutectic melting point of Al-Ag-Cu system.
We are believed to occur by the quaternary eutectic reaction of Al-Ag-Cu-Mg by
adding Mg and Si. The intermetallic compounds in brazed joints were formed
below 560 temperature and to brazed condition for long time(60min) at 560.
But high brazed temperature(560~590), the intermetallic compounds were
not formed. The high bonding strength of the brazed joints was 141MPa at 580
for 10min.
2.1 9
3
3.1 19
3.4 21
3.5 21
4.1 28
4.3 37
4.4 45
4.3 47
5 52
53

.

.
. , , ,



, .

. , ()
, ()
.
(Diffusion bonding),

(Isothermal solidification)
(Transient liquid diffusion bonding)
2
(Brazing) .
450
,
( ) .
,
.
.

, (Al), (Cu), (CuP), (Ni)
, (Ag) . (Gas brazing),
(Furnace brazing), (Insuction brazing),
(Resistence brazing), (Dip brazing) .
,
, , , ,
.

,
.
. radiater, condenser, evaporater,
oil cooler 100%
.
space frame ,
, ,
3
.
(flux) 2 .
(torch), (furnace),
(dip) ,
(VAW), .
,
, ,

. 1975
(drawn cup)
.
Table 1.1
1000∼7000 . 1000, 3000, 4000,
5000 , 2000, 6000, 7000
. 1000, 3000
5000 Mg . 4000 Al-Si
.
Al-Si
Al4047 ( ) 577.
wire, foil, ring, paste ,
sheet .
Table 1.2 .(1)
Cu (2000 ) 5056, 5083 Mg 5000
. 3004, 5050, 7N01
4
Mg 0.8%
Table 1.2 B . Mg 5000
filler wetting ,
.
Mg
. , LNG Tank, , , ,
Tank 5000 ,
, ,
. Al-Si
4047 577

, .
5000
Al5052
. Ag-28Cu Al5052
,
.
7075, 7N01, 7003AA 7xxxAl-Zn
6061, 6063AA 6xxxAl-Mg-Si

4043AA 4xxxAl-Si
3003AA 3xxxAl-Mn

6061, 6063AA 6xxxAl-Mg-Si

4043AA 4xxxAl-Si
3003AA 3xxxAl-Mn

Table 1. 2 Brazebility of aluminum alloys
Note A: Brazeability good B: Brazeability slightly inferior to square standard C: Suitable conditions must be determined by means of preliminary test D: Brazing not recommended
607 ∼646B7N01
477 ∼635D7075
615 ∼650B7003
616 ∼654A6951
588 ∼649B6151
616 ∼654A6063
615 ∼652B6N01
593 ∼652C6061
593 ∼643C5154
568 ∼638D5056
579 ∼641D5083
593 ∼649C5052
624 ∼652B5050
632 ∼654B5005
629 ∼654B3004
643 ∼654A3003
502 ∼638D2024
513 ∼641D2017
510 ∼638D2014
643 ∼657A1100
646 ∼657A1050
8
100
200
300
400
500
600
77xxxxxx
11xxxxxx
33xxxxxx
22xxxxxx
66xxxxxx
55xxxxxx
100
200
300
400
500
600
77xxxxxx
11xxxxxx
33xxxxxx
22xxxxxx
66xxxxxx
55xxxxxx
of aluminum alloys
2.1
(Brazing) .
,

,
()
.

.
.
.


.
(Liquid phase diffusion bonding, Transition liquid phase
bonding) Fig 2.1 .(4)
2 .

(Eutectic reaction)

(Eutectic brazing) . Fig. 2.2 .
10
( 2), (
3) . (Isothermal solidification)
,

.



. 1
.


.
Fig. 2. 1 Mechanism of diffusion bonding process
12
13
2.2
2.2.1

(kinetics) ,
.
. (Tmp) 0.3~0.8 ,
.

.
.
Kirkendall effect


.
(kinetics theroy)
. , (6) .
KTQeDD −= 0
.
14
,
.

.
Kirkendall effect (void)
.
,
.
.
2.2.3
.

.
asperity
. 0.04MPa
20MPa . (7)



.
15


.
.

.
.

. Ti Al Ti Al
Ti
.(4, 8)

.



.

.
16

. Fig.2.3
3 .(9) Ti
,
Ti Zr, Ta, Nb .
, Cu, Fe

Cu, Fe (stainless steel)
. Al


.

.
Ar Ar
Ar
, , ,
, ,
17
2.2.6
.
,
.
2)

. , , ,
~ .
,
-
- ,
-
-
3
.
18
.
.
Fig. 2. 3 Behavior of oxide film at bonding interface
19
Table 3.1 Fig. 3.1 .
Al5052 50mm ,
16 x 16 x 50mm(h) .
1000mesh sand paper
.
600ml, Glycol 360ml, Perchloric acid 60ml 12V,
3 min .
Ag Cu Al ,
. Ag 200
Ag A390
DBSF (diffusion bonding & superplastic forming)
.(11, 12, 13)
(3800psi) , (7 ) . Ag
Al (567) .
Al-Ag-Cu 3 Fig. 3. 3 500
. Ag-
28wt%Cu Al5052
.
20
3.2
Fig. 3.4 .
1MPa
. R type, 0.3mm Fig.3.4

. PID
.
Fig. 3.5 . Fig. 3.5
500 ~ 590, 1min ~ 60min
. 1MPa,
5x10-5 torr .
3.3

100 100
. DTA
DTA 10/min .
21
1
diamond paste Keller .
SEM, EPMA .
3.5
INSTRON CORP. INSTRON 4481
.
Strain rate 10-3/s . Fig. 3.6
.
22
Bal. 0.003 0.27 0.01 0.03 0.01 0.17 2.7Used
Bal. Max
500 600 700
(a) Al-Ag
(b) Ag-Cu
(c) Al-Cu
Fig. 3. 2 Binary phase diagram of (a)Al-Ag, (b)Ag-Cu, (c)Al-Cu system
AgAg CuCu
28%28%
Cu W%Cu W%
25
load
specimen
26
R.T
Time
Brazing pressure : 0.5MPa
(b) dimension of a specimen for tensile test
Fig. 3. 6 Dimension and shape of specimen
Al 5052 Al 505216mm
4.1
Al 5052 Ag-28Cu
(a)Al5052/Ag-28Cu/Al5052 clad (b)Al1050/Ag-28Cu/Al1050 clad
DTA Fig. 4. 1 . Fig. 4. 1 (b)
99.5% Al1050 Ag-28Cu
. Al-Ag-Cu 3
500 .
(a) Al5052
, Al1050 10 490
. Al 5052 Al 1050 Al-Mg
Mg 2.7 wt% Si
. Al 5052 Ag-28Cu Al
Mg, Si .
480
500
Fig. 4. 2 . Fig. 4. 2 (a)

. , (b)
.
. 480
SEM image EPMA
29
Fig. 4. 3 . Fig. 4. 3 (a)
.
20
EPMA Fig. 4. 3 (b) . EPMA 20
Al, Mg, Ag, Cu
.
. Fig. 4.
4 .
Ag Cu .
Mg
. Fig, 4, 5
500 EPMA .
500
. EPMA Al. Mg,
Ag, Cu, Si Ag, Cu
, Al, Mg
.

. Al 5052 Al-Ag-Cu
Al, Cu, Ag Al 5052
Mg, Si Al-Ag-Cu 3
.
30
(a) Al5052 / Ag-28Cu / Al5052
450 550 600 550000
(a) 480 (b) 500
4. 2 Microstructures of the joints brazed at (a) 480, (b) 500
100
32
Fig. 4. 3 Microstructure and EPMA line profile of the joint brazed at 480
(a) SEM image, (b) EPMA line profiles.
Al 5052 Reaction Ag-28Cu Reaction Al 5052
100
AAll
MMgg
AAgg
CCuu
33
Fig.. 4. 4 EPMA mapping-images of the Al5052 joint brazed at 480
Ag28Cu Reaction Al 5052
34
Fig. 4.5 EPMA line profiles of the joint brazed at 500
100
4.2
Fig. 4. 6 500
.

.
.
.
500, 530, 560
Fig. 4. 7 Fig. 4. 8 Fig. 4. 9 . Fig. 4. 7
500 1, 10, 30, 60
.
,
. 1 10 30
. 60
2
2
.
530 Fig. 4. 8
. 30
. 60
.
2
.
36
Fig. 4. 9 560
. Fig. 4. 7 Fig. 4. 8 560
10 ,

. 500 530
60 . 560 60
2
. 2

.
2

.
Fig. 4. 10 470
. 10
. 2
30
. 30
Fig. 4. 11 .
37
4.3
500, 530, 560, 570
Fig. 4. 12 . 1 500, 530,
560, 570

,
. 570 10
30
.
.

.



.
1
2

.
38
100
39
Fig 4.7 Microstructures of the joints brazed for various time at 500
100
40
Fig 4.8 Microstructures of the joints brazed for various time at 530
100
41
Fig 4.9 Microstructures of the joints brazed for various time at 560
(d) 60 min
42
Fig 4.10 Microstructures of the joints brazed for various time at 570
100
(c) 30 min
43
Fig. 4.11 Shape of the brazed Al5052/Ag-28Cu/Al5052 at 570 for 60min
Al5052
Al5052
joints
44
Fig. 4. 12 Tensile strength of the joints brazed as a function of brazing
temperature for various time
20
40
60
80
100
120
140
160
180
200


.
.
Fig. 4. 13 10
.
. 500 530, 560

580 590
. 560 2
.
Fig. 4. 14 560, 580 10
SEM . 560
.
580
.
2 .
EPMA Fig. 4. 15 . Fig. 4. 15
560, 10
. 580, 10

.
46

. 560
2
.

.

.
Fig. 4. 16 .
. 500
530 560
580 10
80% 590
.
2
.
. 2
560
. 590

. 570 30
580 590 10
Fig. 4. 11
.
48
Fig 4.13 Microstructures of Al 5052 joints brazed with Al-28Cu insert metal
at various temperature for 10min.
100
Fig 4.14 SEM microstructures of the joint brazed for 10min.
20
(a) 560, 10min
(b) 580, 10min
Fig. 4. 15 EPMA line profile of the brazed joint for 10min
S i
A g
M g
A l
C u
51
Fig. 4. 16. Tensile strength of the brazed joint as a function of brazing
temperature and brazing time
500 510 520 530 540 550 560 570 580 590
50
100
150
200
180MPa
141MPa
52
1. Al 5052 Ag-28Cu
Al-Ag-Cu 3 490
.
2. 560 2
. 560
.
3. ,
580 10 141MPa .

.
(1989), .700~710
2. “Brazing of Aluminum Alloys”, Metal Hand Book, P. 675~684
3. “ ”,
4.K. Nishiguchi, Y. Takahashi, and A. Seo, “Formation Mechanism of Liquid Phase
by Reaction Diffusion during Diffusion Bonding”, , (1990), p.42~48
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p.738~741
8., “Joining of Titanium and Its Alloys Using Titanium - Base Filler Metals”,

54
9. T.H. CHUANG, M.S. YEH, L.C. TSAO, T.C. TSAI, and C.S. WU, “Development
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Metallurgica Sincia. Vol.19, April, 1983

4.3
4.4
4.3
5.
[Table 1. 2] Brazebility of aluminum alloys
[Table 3. 1] Chemical composition of Al5052 base metal

[Fig. 1. 1] Application of Al alloys assemblies
[Fig. 1. 2] Relationship between strength and solidus temperatures of aluminum alloys
[Fig. 2. 1] Mechanism of diffusion bonding process
[Fig. 2. 2] Concept of diffusion brazing
[Fig. 2. 3] Behavior of oxide film at bonding interface
[Fig. 3. 1] DTA profile of Al5052 base metal
[Fig. 3. 2] Binary phase diagram of (a)Al-Ag, (b)Ag-Cu, (c)Al-Cu system
[Fig. 3. 3] Al-Ag-Cu Ternary Phase diagram
[Fig. 3. 4] Schematic diagram of diffusion bonding system
[Fig. 3. 5] Schematic illustration of experimental procedures
[Fig. 3. 6] Dimension and shape of specimen
[Fig. 4. 1] DTA profile of the clads
[Fig. 4. 2] Microstructures of the joints brazed at (a) 480, (b) 500
[Fig. 4. 3] Microstructure and EPMA line profile of the joint brazed at 480
[Fig. 4. 4] EPMA mapping-images of the Al5052 joint brazed at 480
[Fig. 4. 5] EPMA line profiles of the joint brazed at 500
[Fig. 4. 6] Microstructure of the joint brazed at 500
[Fig. 4. 7] Microstructures of the joints brazed for various time at 500
[Fig. 4. 8] Microstructures of the joints brazed for various time at 530
[Fig. 4. 9] Microstructures of the joints brazed for various time at 560
[Fig. 4. 10] Microstructures of the joints brazed for various time at 570
[Fig. 4. 11] Shape of the brazed Al5052/Ag-28Cu/Al5052 at 570 for 60min
[Fig. 4. 12] Tensile strength of the joints brazed as a function of brazing temperature for various time
[Fig. 4. 13] Microstructures of Al 5052 joints brazed with Al-28Cu insert metal at various temperature for 10min
[Fig. 4. 14] SEM microstructures of the joint brazed for 10min
[Fig. 4. 15] EPMA line profile of the brazed joint for 10min
[Fig. 4. 16] Tensile strength of the brazed joint as a function of brazing temperature and brazing time
1. 1 2. 9 2.1 9 2.2 13 2.2.1 13 2.2.2 14 2.2.3 14 2.2.4 15 2.2.5 16 2.2.6 17 3. 19 3.1 19 3.2 20 3.3 20 3.4 21 3.5 21 4. 28 4.1 28 4.2 35 4.3 37 4.4 45 4.3 47 5. 52 53