the effect of cooling rate and filler metal on the ... · -25-the effect of cooling rate and filler...
TRANSCRIPT
-25-
The Effect of Cooling Rate and Filler Metal on the Properties of Vacuum
Brazed Joint for 2205 Duplex Stainless Steel
Liu-Ho Chiu*, Yi-Chun Ling*, Chia-Hsun Chang*, Wen-Chin Hsieh*
0.85 /s 0.1 /s 0.067 /s UNS31803(2205)
BNi-3 BNi-7
0.067 /s Avesta
2205 GMTC 2205 12.1 17.5 BNi-3 BNi-7 Cu
2205 110~135MPa 50~80MPa 220~250MPa
(0.85 /s)
2205
AbstractThe influence of cooling rates and types of filler on the mechanical properties and corrosion resistance
of the vacuum brazed joints for two 2205 duplex stainless steels was investigated. From the experimental
results, the precipitation of phase was obviously inhibited at a cooling rate of 0.85 /s. The amount of
phase precipitated was increased as the cooling rate was lowered. The shear strengths of vacuum brazed
joints were obtained in the range of 50-80 MPa, 110-135 MPa and 220-250 MPa for using BNi-7, BNi-3
and copper foil as filler, respectively. When the amount of phase was increased, the weight lost of
corroded specimen was increased rapidly. The galvanic corrosion behavior was observed in three brazed
joints using different filler in the chloride solution.
Keywords 2205 duplex stainless steel, vacuum brazed joint, corrosion, phase.
*
Department of Materials Engineering, Tatung University
25 34 89 12
Journal of Chinese Corrosion Engineering, Vol.14 No.4, PP.25~34(2000)
-26-
89 12
(1-3)
316
SMAW GTAW TIG
(3-5)
Potgieter (6) SAF2205
10%H2SO
43.5%NaCl
Wilms (7) Cr Mo
(8 9)
(11)
(GMTC) 65mm
2205 Avesta 2mm
2205 1
2205 55mm 15mm 2mm
Wall Colmonoy BNi-
3 BNi-7 2
10-5
Torr 10-3
Torr
2205 55mm 15mm
2mm 0.02mm
Nicrobraze S-Binder
1
BNi-3 BNi-7 1020 1090
10 0.85 /s( 10-3Torr) 0.1 /s
10-5Torr 0.067 /s 10-5Torr
6mm/min
2205
10wt H2C
2O
4
2H2O 1A/cm2
-27-
2205
40 OM
Groesbeck etching solution 4gNaOH
4gKMnO4
100gH2O
90 150
OM
GMTC 2205 Avesta 2205
ASTM G48 (10)
20mm 15mm 2mm 15mm 10mm
4mm 5min
6 FeCl3
2205
Critical Pitting
Temperatures CPT 47.5
47.5 24
15min
2 2205
2205
65mm Avesta 2205
2205 50
30~50 m Avesta 2205
50
10~20 m
2205 1050
0.85 /s( 10-3Torr) 0.1
/s 10-5Torr 0.067 /s 10-5Torr
2(a)~(c)
GMTC 2205
0.85 /s 0.1 /s 0.067 /s
0.85 /s
(Step Structure)
0.1 /s
(Dual Structure)
0.067 /s
GMTC 2205
2205
(8)
4-(a)~(c) Avesta 2205
1050 10 0.85 /s 0.1 /s
0.067 /s
Avesta 2205
2205 0.1 /s 0.067 /s
(8) 2205 / /
0.1 /s 0.067 /s
(11) 2205
1020~1080 0.25
/s
5(a)~(c) GMTC 2205
Groesbeck solution
Groesbeck solution
0 7.8 17.5
GMTC 2205
-28-
89 12
Avesta 2205 1050
10 0.1 /s 0.067 /s
Groesbeck
2.9 12.1
GMTC 2205
GMTC 2205 Avesta
2205 Mo GMTC 2205
Avesta 2205 GMTC 2205
GMTC 2205 Avesta 2205
single lap
2205 1020 1080 (8)
1020
1080
2205 0.85 /s
0.1 /s 0.067 /s
3 3 BNi-3
110~135MPa BNi-7
50~80MPa
Cu foil
220~250MPa (12) 304
3
Avesta 2205 BNi-3 BNi-7
0.85 /s 0.1 /s
0.067 /s
0.85
/s
BNi-3 BNi-7
Nicrobraz S-Binder
982 888 1020
1083
1090
10-3
Torr 10-5 Torr
0.85 /s
0.85 /s
GMTC 2205 BNi-3
0.1 /s 0.067 /s
(15mm 2mm) 399MPa
359MPa
133MPa 119MPa 0.85 /s
111.4MPa
GMTC 2205
0.067 /s
15
BNi-3
3
2205
-29-
2205
0.85 /s
0.1 /s 0.067 /s 6
FeCl3 6
0.85 /s
Avesta 2205 (0.05
mg/mm2) GMTC 2205 (0.006 mg/mm2)
PRE 1
2 2 0 5
PRE(Pitting Resistance Equivalent) GMTC
2205 Avesta 2205 36.97
33.53
GMTC PRE
6 2205 0.1 /s
0.067 /s
(0.85 /s) Wilms (7)
GMTC 2205
Avesta 2205
7 GMTC 2205 BNi-3 BNi-7
7 GMTC 2205
6
0.02mm
15mm 10mm 4mm
Avesta
2205 BNi-3 BNi-7
GMTC 2205
8
6 FeCl3
47.5 24
GMTC 2205
FeCl3
0.2mg/mm2 0.01 mg/mm2
GMTC 2205
Avesta 2205
9
GMTC 2205
Avesta 2205 2205
-30-
89 12
PRE
0.067 /s Avesta 2205
GMTC 2205 12.1
17.5 6 FeCl3
Avesta 2205
GMTC 2205
NSC89-2216-E-036-
021
1. J. O. Nilsson: Mater. Sci. Techno., 8 (1992) 685.
2. J. Charles, Welding in the World, 36 (1995) 43.
3. R.A. Walker: Mater. Sci. Techno., 4 (1988) 78.
4. P.H. Pumphrey, G.D.W. Smith and M. Prager: Mater.
Sci. Techno., 6 (1990) 209.
5. K. Beklers: Welding in the World, 36 (1995) 111.
6. Potgieter: British Corrosion Journal, 27(3) (1992)
219.
7. M. E. Wilms, V. J. Gadgil, J. M. Krougman and F. P.
IJsseling: Corrosion Science, 36 (1994) 871.
8. , , : , 12(2) (1998)33.
9. , , : , 12(4)
(1998),29,
10. ASTM G48-92, 1992, ASTM.
11. , : 88 ,
(1999).
12. , , 1999, p. 32.
13. C. O. A. Olsson, P. E. Arnvig: Corrosion Science,
37 (1995) 1201.
1 (wt%)
Table1 Chemical compositions of two duplex stainless
steels (wt )
Fe C Si Mn Cr Ni Mo N Cu
GMTC 64.2 0.04 0.5 1.65 22.7 5.4 3.45 0.18 0.06
Avesta 65.9 0.02 0.5 1.22 22.4 5.1 2.5 0.18 0.27
2 (wt%)
Table 2 Chemical compositions of filler metal
Filler Chemical Compositions
Cr B Si Fe P Ni Cu
BNi-3 -- 3.13 4.5 0.5 0.02 bal --
BNi-7 14.0 0.01 0.10 0.2 10.1 bal --
Cu foil -- -- -- 0.1 -- 0.2 bal
3
Table 3 Shear strength of vacuum brazed joints for two
duplex stainless steels
Material Filler Metal Cooling Rate Shear Strength
( /s) (MPa)
BNi-3 0.85 111.4
0.1 399*(133)
0.067 359*(118)
BNi-7 0.85 78.8
0.1 62.7
0.067 62.1
GMTC Cu foil 0.85 172.7
2205 0.1 458*(153)
DSS 0.067 359*(119)
BNi-3 0.85 117.8
0.1 135.3
0.067 116.1
BNi-7 0.85 68.2
0.1 54.7
0.067 46.4
Cu foil 0.85 200
0.1 236
0.067 226
*Fractured at Duplex Stainless Steel; Strength was
obtained by divided the fractured area, 15mm 2mm,
and the ( ) value implied the value divided the brazed
area.
-31-
2205
1
Fig. 1 Schematics of the brazed joints.
(a)
(b)
2 2205
(a) GMTC, (b) Avesta
Fig. 2 Microstructures of two as-received duplex
stainless steels electroetched in oxalic acid: (a)
GMTC 2205 and (b) SAF 2205.
-32-
89 12
(a)
(b)
(c)
3 GMTC 2205 1050
(a) 0.85 /s, (b) 0.1 /s, (c) 0.067 /s
Fig. 3 Microstructures of GMTC 2205 duplex stainless
steel after 1050 solution treatment for different
cooling rates, (a) 0.85 /s, (b) 0.1 /s, (c) 0.067
/s, electroetched in oxalic acid.
(a)
(b)
(c)
4 Avesta 2205 1050
(a) 0.85
/s, (b) 0.1 /s, (c) 0.067 /s
Fig.4 Microstructures of Avesta 2205 duplex stainless
steel after 1050 solution treatment for different
cooling rates (a) 0.85 /s, (b) 0.1 /s, (c) 0.067
/s, electroetched in oxalic acid.
-33-
2205
(a)
(b)
(c)
5 GMTC 2205 1050
Groesbeck (a)
0.85 /s, (b) 0.1 /s, (c) 0.067 /s
Fig.5 Microstructures of GMTC 2205 duplex stainless
steel after 1050 solution treatment for different
cooling rates, (a) 0.85 /s, (b) 0.1 /s, (c) 0.067
/s, etched in Groesbeck solution.
6 2205 6 FeCl3
47.5 24
Fig. 6 Weight lost of DSS specimens immersed in 6
FeCl3 solution at 47.5 for 24 hours.
7 GMTC 2205 6
FeCl3 47.5 24
Fig. 7 Weight lost of GMTC 2205 DSS brazed joints
immersed in 6 FeCl3 solution at 47.5 for 24
hours.
-34-
89 12
9
(a) BNi-3 (b) BNi-7 (c) Cu foil
Fig. 9 The corroded morphologies of brazed joint after
the immersion tests, (a) BNi-3, (b) BNi-7, (c) Cu
foil.
8
6 FeCl3
47.5 24
Fig. 8 Weight lost of two air cooled DSS and their
brazed joints immersed in 6 FeCl3
solution at
47.5 for 24 hours.
(a)
(b)
(c)