Fe基非晶涂层在Na_(2)SO_(4)+K_(2)SO_(4)和Na_(2)SO_(4)+NaCl混合盐中的热腐蚀行为研究  

Hot Corrosion Behavior of Fe-based Amorphous Coatings in Mixed Salts of Na_(2)SO_(4)+K_(2)SO_(4)and Na_(2)SO_(4)+NaCl

作　　者：张勇康 翟海民 李旭强 李文生[1,2] ZHANG Yongkang;ZHAI Haimin;LI Xuqiang;LI Wensheng(State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;College of Physics and Electronic Engineering,Northwest Normal University,Lanzhou 730070,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]西北师范大学物理与电子工程学院,兰州730070

出　　处：《中国腐蚀与防护学报》2025年第1期92-102,共11页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(52265024);兰州市青年科技人才创新项目(2023-QN-92)。

摘　　要：垃圾焚烧过程中存在的S和Cl等元素影响了锅炉管道的使用。为解决这一问题,采用爆炸喷涂技术在316L不锈钢基体上制备了Fe基非晶涂层,研究了涂层在K_(2)SO_(4)+50%(质量分数)Na_(2)SO_(4)和NaCl+50%(质量分数)Na_(2)SO_(4)混合盐中450和550℃下的热腐蚀行为。结果表明,与316L不锈钢相比,涂层增重降低,耐热腐蚀性好。450℃热腐蚀90 h后,涂层腐蚀轻微,生成少量腐蚀产物。而550℃时,涂层表面变得更加粗糙且出现明显的开裂现象。NaCl+50%Na_(2)SO_(4)对涂层的热腐蚀破坏作用大于K_(2)SO_(4)+50%Na_(2)SO_(4)。这主要是由于NaCl与涂层表面氧化层反应生成的Cl_(2)可穿透氧化层与未腐蚀涂层发生反应,导致氧化层形成裂纹,加速涂层的热腐蚀行为。Waste incineration is an alternative way of heating,which can reduce the dependence on fossil fuels and carbon dioxide emissions,but the elements such as S and Cl present in the waste incineration process affect the use of boiler pipes.With the increase of temperature,the hot corrosion phenomenon is intensified,and the hot end pipe component damage is also aggravated,which may cause catastrophic accidents.Therefore,the corrosion resistant protective coating on superheater tube is an effective method to solve this problem.The Fe-based amorphous coating(AMC)has the advantages of low cost and strong corrosion resistance:Firstly,the Fe-based AMC uses Fe-based multi-metallic materials as raw materials,which has lower cost than other kinds of amorphous materials;moreover,this kind of coating has excellent anti-corrosion,wear-resistant and easy to repair.Herein,a novel Fe-based AMC were prepared on 316L stainless steel substrate by detonation spraying technology.The corrosion behavior of AMC coating/316L stainless steel covered with deposit of 2 mg/cm^(2) mixed salts of either K_(2)SO_(4)+50%Na_(2)SO_(4)or NaCl+50%Na_(2)SO_(4)(in mass fraction)was assessed at 450 and 550 ℃ in air respectively.Results indicate that the coating exhibited good resistance to mixed salts corrosion superior to that of 316L stainless steel substrate.After mixed salts corrosion at 450 ℃ for 90 h,the coating showed slight corrosion and formation of minimal corrosion products.After corrosion at 550 ℃,the coating surface became rougher with visible cracking.The corrosion impact of NaCl+50%Na_(2)SO_(4)on the coating was found to be more severe than that of K_(2)SO_(4)+50%Na_(2)SO_(4).This is primarily due to the reaction of NaCl with the oxide layer on the coating surface;leading to the formation of Cl_(2).Cl_(2)can penetrate the formed oxide scale,react with the uncorroded coating,induce cracks in the oxide scale,and finally accelerate the corrosion process of the coating.

关 键 词：爆炸喷涂 Fe 基非晶涂层 热腐蚀 氧化层 

分 类 号：TG174[金属学及工艺—金属表面处理]