Comparison of the Stress Corrosion Cracking Behaviour of AISI 304 Pipes Welded by TIG and LBW

doi:10.1007/s40195-020-01126-9

Abstract

Abstract:

The stress corrosion cracking (SCC) behaviour of AISI 304 pipe girth welds which were welded by a single-pass laser beam welding (LBW) and a multi-pass tungsten inert gas welding (TIG), respectively, was studied by the slow strain rate tests combined with the electrochemical corrosion tests. The results show that fracture of both the TIG joint and LBW joint occurs in the heat-affected zone (HAZ). According to the electron-backscattered diffraction observation of the microstructures, comparison of potentiodynamic polarization curves and X-ray photoelectron spectroscopy analysis of corrosion products on HAZs of the two joints after the electrochemical tests, the LBW joint exhibits better SCC resistance than the TIG joint in corrosion environments, due to the synthetic effect of more Cr₂O₃ in corrosion products, finer grains, lower residual strain and higher δ-ferrite content in its HAZ. Although the TIG joint has better mechanical property, considering lower SCC susceptibility and higher production efficiency of the LBW joint, the LBW promisingly replaces the TIG for welding of AISI 304 pipes in the nuclear power industry.

Key words: Laser beam welding, Slow strain rate test, Stress corrosion cracking, Tungsten inert gas welding, AISI 304 stainless steel

Ji-Jin Xu, Shuai Wang, Ze Chai, Chun Yu, Jun-Mei Chen, Hao Lu. Comparison of the Stress Corrosion Cracking Behaviour of AISI 304 Pipes Welded by TIG and LBW[J]. Acta Metallurgica Sinica (English Letters), 2021, 34(4): 579-589.

Figures/Tables 14

Table 1 Chemical compositions of base metal and filler (wt%)

Materials	C	Cr	Ni	Si	Mn	Mo	Cu	Nb	Fe
AISI 304	0.06	18.5	8.3	0.5	1.5	0.3	0.4	0.03	Bal.
ER308L	0.02	18.1	9.7	0.6	1.9	0.2	0.01	0.007	Bal.

Table 2 Welding process parameters

Methods	Groove type	Weld pass	Filler	Power (P/kW)	Welding speed (v/mm s^-1)	Shield gas	Heat input (q/kJ mm^-1)
LBW	I-type	Single-pass	-	11	8	N₂	1.375
TIG	30°-V-type	Multi-pass	ER308L	2.8	2.2	Ar	1.270 (one of nine passes)

Fig. 1 Sketch of SSRT specimen (mm)

Fig. 2 Stress-strain curves of two joints in air and in simulated PRW environment

Table 3 Corrosion properties of the two joints

Specimen	In air		In simulated primary water		$I_{\sigma} \left( \% \right)$	$I_{\eta} \left( \% \right)$	ISSRT (%)
Specimen	$\sigma_{\text{a}}$ (MPa)	$\eta_{\text{a}}$ (%)	$\sigma_{\text{w}}$ (MPa)	$\eta_{\text{w}}$ (%)	$I_{\sigma} \left( \% \right)$	$I_{\eta} \left( \% \right)$	ISSRT (%)
LBW joint	470	31.2	466	28.8	0.85	7.7	2.7
TIG joint	534	38.9	529	34.7	1.12	9.4	3.9

Fig. 3 Microhardness distribution along the transverse direction

Fig. 4 Longitudinal fracture macrographs of a the LBW joint, b the TIG joint

Fig. 5 SEM fractographs in air: a overview of the LBW joint, b at the rim area of the LBW joint, c overview of the TIG joint, d at the rim area of the TIG joint

Fig. 6 SEM fractographs in simulated PRW environment: a overview of the LBW joint, b at the rim area of the LBW joint, c overview of the TIG joint, d at the rim area of the TIG joint

Fig. 7 Potentiodynamic polarization curves of the welded joints

Fig. 8 IPF maps of a the LBW joint, b the TIG joint, (100) pole figures of c the BM of AISI 304 steel, d the LBW weld metal and e the TIG

Fig. 9 δ-Ferrite distribution in a the LBW joint, b the TIG joint; optical microphotographs for c the LBW joint, d the TIG joint

Fig. 10 EBSD KAM maps of a the LBW joint, b the TIG joint

Fig. 11 XPS high-resolution spectra of different elements in the oxide film: a Cr 2p of the LBW joint, b Cr 2p of the TIG joint, c Fe 2p of the LBW joint, d Fe 2p of the TIG joint, e Ni 2p of the LBW joint, f Ni 2p of the TIG joint, g O 1s of the LBW joint, h O 1s of the TIG joint

References 29

[1]	H.L. Ming, Z.M. Zhang, P.Y. Xiu, J.Q. Wang, E.H. Han, W. Ke, M.X. Su, Acta. Metall. Sin. (Engl. Lett.) 29, 848 (2016) DOI URL
[2]	S. Sabooni, F. Karimzadeh, M.H. Enayati, A.H.W. Ngan, H. Jabbari, Mater. Charact. 109 138 (2015) DOI URL
[3]	J.M. Sun, X. Liu, Y. Tong, D. Deng, Mater. Des. 63 519 (2014)
[4]	J. Yan, M. Gao, X. Zeng, Opt. Lasers Eng. Eng. 48 512 (2010)
[5]	C.A. Loto, Int. J. Adv. Manuf. Technol. 93 3567 (2017)
[6]	G.J. Abraham, V. Kain, G.K. Dey, V.S. Raja, Corros. Sci. 93 1 (2015)
[7]	G.J. Abraham, R. Bhambroo, V. Kain, G.K. Dey, V.S. Raja, J. Mater. Eng. Perform. 22 427 (2012)
[8]	A.-H.I. Mourad, A. Khourshid, T. Sharef, Mater. Sci. Eng. A. 549 105 (2012) DOI URL
[9]	I.A. Orsi, L.B. Raimundo, O.L. Bezzon, M.A.A. Nobilo, S.E. Kuri, C.A.D. Rovere, V.O. Pagnano, J. Prosthodontics 20, 628 (2011)
[10]	X. Xie, D. Ning, B. Chen, S. Lu, J. Sun, Corros. Sci. 112 576 (2016) DOI URL
[11]	J.Z. Lu, H. Qi, K.Y. Luo, M. Luo, X.N. Cheng, Corros. Sci. 80 53 (2014)
[12]	P. De Tiedra, Ó. Martín, Mater. Des. 49 103 (2013)
[13]	J.J. Xu, J.Y. Chen, Y. Duan, C. Yu, J.M. Chen, H. Lu, J. Mater. Process. Technol. 248 178 (2017)
[14]	Z. Chai, C. Jiang, Electrochim. Acta. 294 11 (2019) DOI URL
[15]	Y. Tsuchiya, F. Kano, N. Saito, M. Ookawa, J. Kaneda, Corrosion and SCC properties of fine grain stainless steel in subcritical and supercritical pure water, in Paper Presented at the Corrosion 2007, Nashville, 11-15 March 2007
[16]	K. Kako, Y. Miyahara, T. Arai, M. Mayuzumi, Denryoku Chuo Kenkyusho Hokoku 16 1 (2009)
[17]	J. Hou, Q.J. Peng, Z.P. Lu, T. Shoji, J.Q. Wang, E.H. Han, W. Ke, Corros. Sci. 53 1137 (2011)
[18]	Y. Chen, B. Alexandreanu, W.Y. Chen, K. Natesan, Z. Li, Y. Yang, A.S. Rao, J. Nucl. Mater. 466 560 (2015)
[19]	H. Abe, Y. Watanabe, J. Nucl. Mater. 424 57 (2012)
[20]	C. Ma, Q.J. Peng, J.N. Mei, E.H. Han, W. Ke, J. Mater. Sci. Technol. 34 1823 (2018)
[21]	Z.P. Lu, J.J. Chen, T. Shoji, Y. Takeda, S. Yamazaki, J. Nucl. Mater. 465 471 (2015)
[22]	R.K. Gupt, N. Birbills, Corros. Sci. 92 1 (2015)
[23]	M. Kanzaki, Y. Masaki, T. Kudo, Corrosion 71, 1027 (2015)
[24]	J.L. Lv, T.X. Liang, C. Wang, L.M. Dong, Mater. Sci. Eng. C. 360 403 (2016)
[25]	A.A. Hermas, Corros. Sci. 50 2498 (2008
[26]	E. Unveren, E. Kemnitz, S. Hutton, Surf. Interface Anal. 36 92 (2004)
[27]	Z. Shen, D. Du, L. Zhang, S. Lozano-Perez, Corros. Sci. 148 213 (2019)
[28]	L. Fan, Z. Liu, W. Guo, J. Hou, C. Du, X. Li, Acta. Metall. Sin. (Engl. Lett.) 7, 866 (2015)
[29]	J. Shao, C. Du, X. Zhang, L. Cui, Acta. Metall. Sin. (Engl. Lett.) 32, 89 (2019) DOI URL