Correlation Between Microstructure and Corrosion Behavior of Two 90Cu10Ni Alloy Tubes

• Published in: Acta metallurgica sinica : English letters Vol. 27; no. 4; pp. 730 - 738
• Main Authors: Ma, Aili, Jiang, Shengli, Zheng, Yugui, Yao, Zhiming, Ke, Wei, Xia, Shuang
• Format: Journal Article
• Language: English
• Published: Heidelberg The Chinese Society for Metals 01.08.2014; Springer Nature B.V
• Subjects: Alloys; Boundaries; Characterization and Evaluation of Materials; Chemistry and Materials Science; Copper base alloys; Correlation; Corrosion; Corrosion and Coatings; Corrosion resistance; Corrosion tests; Electron back scatter diffraction; Electron backscatter diffraction; Experiments; Flow velocity; Grain boundaries; Grain size; Grooves; Hydrochloric acid; Immersion tests (corrosion); Marine corrosion; Materials Science; Metallic Materials; Morphology; NaCl溶液; Nanotechnology; Organometallic Chemistry; Scanning electron microscopy; Seawater; Service life; Silicon carbide; Spectroscopy/Spectrometry; Tribology; Tubes; 使用寿命; 合金管; 显微组织; 晶界特征分布; 电子背散射衍射; 腐蚀行为; 随机边界; Corrosion resistance; Σ3 boundary; Electron backscattered diffraction; 90Cu10Ni alloy; Grain boundary; Twin
• ISSN: 1006-7191; 2194-1289
• DOI: 10.1007/s40195-014-0111-x

Two kinds of 90Cu10 Ni tubes with different service lives（more than 3 years and only 1 year,respectively）under identical working conditions were studied by an immersion test in a 3.5 wt% NaCl solution and the electron backscattered diffraction（EBSD） technique.The morphology after immersion showed severer corrosion attack at the grain boundaries of the tube with shorter service life compared with the tube with longer service life.The grain boundary characterization distributions（GBCDs） of the two tubes obtained by EBSD revealed more Σ3 boundaries and twins,and larger random boundary meshes in the tube with longer service life.A short immersion test in a modified Livingston＇s solution was conducted to evaluate the tendency to corrosion attack of different types of the grain boundaries.SEM and AFM were used to characterize the corrosion morphologies of the boundaries.A strong correlation between varying depths of corrosion grooves and types of the grain boundaries was obtained.The influence of deviation angle of low Σ boundaries on corrosion resistance of the grain boundaries was also discussed.It is concluded that a special ‘‘grain boundary engineering＇＇（GBE） treatment has been performed on the tube with longer service life.It is proposed that the optimized GBCD is responsible for the better service performance of the tube.