第8期 刘飞华等：690合金的Pb致应力腐蚀行为 ·1039· 化层中会造成电导率的增加，会降低钝化膜的保护 341(2/3):169 性，从而使得腐蚀速率增加 [4]Peng B,Lu B T,Luo J L,et al.Investigation of passive 690合金的Pb致应力腐蚀机理至今尚不明确， films on nickel Alloy 690 in lead-containing environments. J Nucl Mater,2008,378(3:333 有文献报道690合金的Pb致应力腐蚀机理，认为 5]Hu Y S,Wang J Q,Ke W,et al.Corrosion behavior of 表面应力是导致初始裂纹的形成原因，16-1)，但这 Alloy 690TT in high temperature lead-containing caustic 就无法区别有Pb和无Pb环境下的应力腐蚀裂纹 solution.J Chin Soci Corros Prot,2010,30(6):427 形式的不同.比较690合金在含Pb高温高压水环 (胡轶嵩，王俭秋，柯伟，等.690TT合金在高温含铅碱液中 境中腐蚀产物膜的表面和截面形貌分析，发现含Pb 的腐蚀行为.中国腐蚀与防护学报，2010,30(6)：427) 环境中的腐蚀产物膜较厚，并且在腐蚀产物膜中有 [6]Hua F H,Huang C B,Lu Z P,et al.Lead-induced stress corrosion cracking of alloys 800,600 and 690.Corros Prot, Pb的存在.Pb掺杂到腐蚀产物膜中，导致腐蚀产 2001,22(11):483 物膜的电导率增大，保护性变差，腐蚀的加快.基体 (华惠中，黄春波，吕战鹏，等.800、600和690合金的铅致 的薄弱处可以成为裂纹优先形成位置，微裂纹形成 应力腐蚀破裂.腐蚀与防护，2001,22(11)：483) 以后，Pb扩散到裂纹尖端处，腐蚀继续进行，裂纹 [7]Staehle R W.Clues and issues in the SCC of high nickel alloys associated with dissolved lead /Proceeding of the 内堆积腐蚀产物，腐蚀产物与及基体的膨胀系数差 12th International Conference on Environmental Degra- 异较大，裂纹扩展，从而形成穿晶型腐蚀裂纹.Pb dation of Materials in Nuclear Power System-Water Re- 的存在导致690合金腐蚀速率的加快可能是形成穿 actors.Salt Lake City,2005:1163 晶型应力腐蚀裂纹的重要原因. [8]Kim J S,Yi Y S,Kwon O C,et al.Performance of NiB inhibitor for PbSCC of Alloy 600 in Pb-contaminated wa- 3结论 ter and caustic solutions.Metal Mater Int,2008.14(3): 341 (1)690合金在含1000mgL-1Pb的高温高压 [9]Huang S S,Kim H P,Lim Y S,et al.Transgranular SCC 水环境中经历4400h的实验会发生应力腐蚀开裂 mechanism of thermally treated Alloy 600 in alkaline wa- 现象，应力腐蚀裂纹表现为穿晶型，裂纹内腐蚀产 ter containing lead.Corros Sci,2007,49(10):3797 物中有Pb的存在. [10 Kim S W,Kim H P.Electrochemical noise analysis of Pb- SCC of Alloy 600 SG tube in caustic environments at high (2)表面生成的腐蚀产物膜内层富Cr、外层富 temperature.Corros Sci,2009,51(1):191 Ni,并且腐蚀产物内存有Pb,应力腐蚀裂纹内部堆 [11]Huang J B,Wu X Q,Han E H.Electrochemical proper- 积着一定数量的腐蚀产物.Pb在表面腐蚀产物膜的 ties and growth mechanism of passive films on Alloy 690 生成和裂纹形成过程中扮演重要的作用. in high-temperature alkaline environments.Corros Sci, (3)690合金管的内外表面腐蚀形貌差异明显， 2010,52(10):3444 主要是由于内外表面的状态不同造成的. [12 Dan T,Shoji T,Lu Z P,et al.Effects of hydrogen on the anodic behavior of Alloy 690 at 60 C.Corros Sci.2010 (4)Pb的存在导致690合金的腐蚀速率加快， 52(4):1228 并且掺杂在腐蚀产物膜中，这会使得钝化膜的保护 [13 Jiao S Y,Zhang M C,Zheng L,et al.Investigation of car- 性变差，裂纹中腐蚀产物与基体膨胀系数的差异使 bide precipitation process and chromium depletion during 得裂纹快速扩展从而导致应力腐蚀裂纹形成。 thermal treatment of Alloy 690.Metall Mater Trans A, 2010,41(1):26 [14]Sun M C,Wu X Q,Zhang Z E,et al.Analyses of oxide 参考文献 films grown on Alloy 625 in oxidizing supercritical water. J Surpercrit Fluid,2008,47(2):309 [1]Was G S.Grain boundary chemistry and intergranular [15]Ahn S J,Rao V S,Kon H S,et al.Effects of PbO on fracture in austenitic nickel base alloys:a review.Corro- the repassivation kinetics of Alloy 690.Corros Sci.2006. siom,1990,46(4):319 48(5):1137 (2]Angeliu T M,Was G S.Behavior of grain boundary chem- [16]Lu B T,Luo J L,Lu Y C.Correlation between film rup istry and precipitates upon thermal treatment of con- ture ductility and PbSCC of Alloy 800.Electrochim Acta. trolled purity Alloy 690.Metall Trans A,1990,21 (8): 2008,53(12:4122 2097 [17]Kim D J,Kwon H C,Kim H W,et al.Oxide properties [3]Kim U C,Kim K M,Lee E H.Effects of chemical com- and stress corrosion cracking behaviour for Alloy 600 in pounds on the stress corrosion cracking of steam generator leaded caustic solutions at high temperature.Corros Sci, tubing materials in a caustic solution.J Nucl Mater,2005 2011,53(4):1247第 8 期 刘飞华等：690 合金的 Pb 致应力腐蚀行为 1039 ·· 化层中会造成电导率的增加，会降低钝化膜的保护 性，从而使得腐蚀速率增加. 690 合金的 Pb 致应力腐蚀机理至今尚不明确， 有文献报道 690 合金的 Pb 致应力腐蚀机理，认为 表面应力是导致初始裂纹的形成原因[7,16−17]，但这 就无法区别有 Pb 和无 Pb 环境下的应力腐蚀裂纹 形式的不同. 比较 690 合金在含 Pb 高温高压水环 境中腐蚀产物膜的表面和截面形貌分析，发现含 Pb 环境中的腐蚀产物膜较厚，并且在腐蚀产物膜中有 Pb 的存在. Pb 掺杂到腐蚀产物膜中，导致腐蚀产 物膜的电导率增大，保护性变差，腐蚀的加快. 基体 的薄弱处可以成为裂纹优先形成位置，微裂纹形成 以后，Pb 扩散到裂纹尖端处，腐蚀继续进行，裂纹 内堆积腐蚀产物，腐蚀产物与及基体的膨胀系数差 异较大，裂纹扩展，从而形成穿晶型腐蚀裂纹. Pb 的存在导致 690 合金腐蚀速率的加快可能是形成穿 晶型应力腐蚀裂纹的重要原因. 3 结论 (1) 690 合金在含 1000 mg·L −1 Pb 的高温高压 水环境中经历 4400 h 的实验会发生应力腐蚀开裂 现象，应力腐蚀裂纹表现为穿晶型，裂纹内腐蚀产 物中有 Pb 的存在. (2) 表面生成的腐蚀产物膜内层富 Cr、外层富 Ni，并且腐蚀产物内存有 Pb，应力腐蚀裂纹内部堆 积着一定数量的腐蚀产物. Pb 在表面腐蚀产物膜的 生成和裂纹形成过程中扮演重要的作用. (3) 690 合金管的内外表面腐蚀形貌差异明显， 主要是由于内外表面的状态不同造成的. (4) Pb 的存在导致 690 合金的腐蚀速率加快， 并且掺杂在腐蚀产物膜中，这会使得钝化膜的保护 性变差，裂纹中腐蚀产物与基体膨胀系数的差异使 得裂纹快速扩展从而导致应力腐蚀裂纹形成. 参 考 文 献 [1] Was G S. Grain boundary chemistry and intergranular fracture in austenitic nickel base alloys: a review. Corro￾sion, 1990, 46(4): 319 [2] Angeliu T M, Was G S. Behavior of grain boundary chem￾istry and precipitates upon thermal treatment of con￾trolled purity Alloy 690. Metall Trans A, 1990, 21 (8): 2097 [3] Kim U C, Kim K M, Lee E H. Effects of chemical com￾pounds on the stress corrosion cracking of steam generator tubing materials in a caustic solution. J Nucl Mater, 2005, 341(2/3):169 [4] Peng B, Lu B T, Luo J L, et al. Investigation of passive films on nickel Alloy 690 in lead-containing environments. J Nucl Mater, 2008, 378(3): 333 [5] Hu Y S, Wang J Q, Ke W, et al. Corrosion behavior of Alloy 690TT in high temperature lead-containing caustic solution. J Chin Soci Corros Prot, 2010, 30(6): 427 (胡轶嵩, 王俭秋, 柯伟, 等. 690TT 合金在高温含铅碱液中 的腐蚀行为. 中国腐蚀与防护学报, 2010, 30(6): 427) [6] Hua F H, Huang C B, Lu Z P, et al. Lead-induced stress corrosion cracking of alloys 800, 600 and 690. Corros Prot, 2001, 22 (11): 483 (华惠中, 黄春波, 吕战鹏, 等. 800、600 和 690 合金的铅致 应力腐蚀破裂. 腐蚀与防护, 2001, 22(11): 483) [7] Staehle R W. Clues and issues in the SCC of high nickel alloys associated with dissolved lead // Proceeding of the 12th International Conference on Environmental Degra￾dation of Materials in Nuclear Power System-Water Re￾actors. Salt Lake City, 2005: 1163 [8] Kim J S, Yi Y S, Kwon O C, et al. Performance of NiB inhibitor for PbSCC of Alloy 600 in Pb-contaminated wa￾ter and caustic solutions. Metal Mater Int, 2008, 14(3): 341 [9] Huang S S, Kim H P, Lim Y S, et al. Transgranular SCC mechanism of thermally treated Alloy 600 in alkaline wa￾ter containing lead. Corros Sci, 2007, 49(10): 3797 [10] Kim S W, Kim H P. Electrochemical noise analysis of Pb￾SCC of Alloy 600 SG tube in caustic environments at high temperature. Corros Sci, 2009, 51(1): 191 [11] Huang J B, Wu X Q, Han E H. Electrochemical proper￾ties and growth mechanism of passive films on Alloy 690 in high-temperature alkaline environments. Corros Sci, 2010,52(10): 3444 [12] Dan T, Shoji T, Lu Z P, et al. Effects of hydrogen on the anodic behavior of Alloy 690 at 60 ℃. Corros Sci, 2010, 52(4): 1228 [13] Jiao S Y, Zhang M C, Zheng L, et al. Investigation of car￾bide precipitation process and chromium depletion during thermal treatment of Alloy 690. Metall Mater Trans A, 2010, 41(1): 26 [14] Sun M C, Wu X Q, Zhang Z E, et al. Analyses of oxide films grown on Alloy 625 in oxidizing supercritical water. J Surpercrit Fluid, 2008, 47(2): 309 [15] Ahn S J, Rao V S, Kon H S, et al. Effects of PbO on the repassivation kinetics of Alloy 690. Corros Sci, 2006, 48(5): 1137 [16] Lu B T, Luo J L, Lu Y C. Correlation between film rup￾ture ductility and PbSCC of Alloy 800. Electrochim Acta, 2008, 53(12): 4122 [17] Kim D J, Kwon H C, Kim H W, et al. Oxide properties and stress corrosion cracking behaviour for Alloy 600 in leaded caustic solutions at high temperature. Corros Sci, 2011, 53(4): 1247