表面技术2025，Vol.54Issue(12)：72-84,13.DOI:10.16490/j.cnki.issn.1001-3660.2025.12.006
Ni-Cu-P复合镀层在硫酸盐还原菌环境下的腐蚀特性
Corrosion Characteristics of Ni-Cu-P Composite Coatings in Environments of Sulphate-Reducing Bacteria
摘要
Abstract
To improve the corrosion resistance of carbon steel against microorganisms,the corrosion behavior of sulfate-reducing bacteria(SRB)on nickel-phosphorus coatings is simulated by experiment,and the corrosion process and differences of SRB on N80 steel,Ni-P and Ni-P/Ni-Cu-P composite coatings are investigated.Ni-P/Ni-Cu-P composite coatings are prepared on the N80 steel substrate using continuous chemical plating process.The corrosion behavior of the coatings and N80 steel in the SRB environment is investigated by biological culture technology,static hanging experiments,and electrochemical tests.Combined with NaS2O3 titration technology,SEM,XRD,and XPS analysis methods are used to characterize and analyze the corrosion behavior and differences of different coating layers.As a result,in terms of coating preparation performance,the surface structure of the Ni-P/Ni-Cu-P composite coatings is more delicate,uniform and dense.No obvious pinholes or defects are found on the surface under 1 000 times magnification,and the surface contact angle is large,which plays a role of hydrophobicity.At the same time,the porosity is very low,only 0.4 N/cm2.After immersion corrosion for 14 days,the corrosion rate of N80 steel is 0.049 1 mm/a,that of the Ni-P coatings is approximately 0.026 9 mm/a,and that of the Ni-P/Ni-Cu-P composite coatings is 0.005 1 mm/a.The number of SRB growths and S2-content in the copper-containing composite coating environment is consistently lower than those in other sample groups,significantly shortening the SRB growth cycle.The samples of N80 steel and Ni-P single coating surfaces show obvious pitting corrosion,while the composite coating samples have a smoother and flatter surface with no significant voids observed.As corrosion progresses,the impedance of N80 steel and Ni-P coatings first increases and then decreases,consistent with the SRB growth pattern,whereas the impedance of the composite coatings sequentially decreases without being affected by the number of SRBs.Comparing the XRD spectra of the composite coatings before and after corrosion,the Ni-P/Ni-Cu-P composite coatings show a significant shift in the diffraction angles and a narrowing of the peak shapes,indicating a decrease in lattice constant.Since the atomic radius of Cu filling the 4s orbital is larger than that of Ni,this suggests that Cu diffuses or migrates from the Ni-Cu solid solution,leading to a phase transformation during the corrosion process.The Ni-P/Ni-Cu-P composite coatings have a lower porosity and higher contact angle,which reduces the adsorption of SRB bacteria;furthermore,Cu ions are released from the alloy surface into the solution or within the SRB cells disrupt the cell membrane and cell wall,causing structural damage to SRB bacteria,leading to noticeable shrinkage,damage,and leakage of cellular contents,thereby reducing the activity of the SRB system and accelerating microbial degradation.At the same time,Ni-Cu-P belongs to the anodic coating,forming a structure with a large anode and a small cathode compared with the inner Ni-P coating,which is relatively safe and reduces the anodic dissolution rate,preventing damage to the composite structure's surface in the short term.Consequently,the longitudinal corrosion of the coating becomes transverse corrosion,delaying the penetration of corrosion to the entire coating layer and sacrificing the top layer to protect the bottom layer,thereby delaying substrate corrosion.Moreover,the high phosphorus amorphous structure and the dense surface passive film of the composite coating significantly hinder the entry and exit of ions and electrons,increasing the film resistance,resulting in extremely low corrosion rates and low pitting probabilities for Ni-P/Ni-Cu-P composite coatings in mixed solutions of SRB and formation water.关键词
Ni-Cu-P复合镀层/硫酸盐还原菌(SRB)/微生物腐蚀/腐蚀防护Key words
Ni-Cu-P composite coating/sulphate reducing bacteria(SRB)/microbial corrosion/corrosion protection分类
矿业与冶金引用本文复制引用
张雅妮,张成鑫,宋伟,段博文,刘波,樊冰,王思敏..Ni-Cu-P复合镀层在硫酸盐还原菌环境下的腐蚀特性[J].表面技术,2025,54(12):72-84,13.基金项目
国家自然科学基金(52401111) （52401111）
陕西省自然科学基础研究计划项目(2024JC-YBQN-0457) （2024JC-YBQN-0457）
西安市科技计划项目(24GXFW0075)National Natural Science Foundation of China(52401111) （24GXFW0075）
Natural Science Basic Research Project of Shaanxi Province(2024JC-YBQN-0457) （2024JC-YBQN-0457）
Xi'an Science and Technology Plan Project(24GXFW0075) （24GXFW0075）
