高速电弧喷涂Fe—Al／Cr3C2RE复合涂层抗高温腐蚀性能探讨

使用Fe—Al／Cr3C2RE粉芯喷涂丝材,结合高速电弧喷涂技术（HVAS）在20钢上制备Fe～Al／Cr3C2RE复合涂层,同时以Fe—Al／Cr3C2涂层为比较。通过对涂层进行650℃下涂盐热腐蚀试验,借助扫描电镜观测腐蚀前后涂层表面形貌,利用XRD确定涂层的相组成,对腐蚀后涂层截面进行EDS分析。结果表明：Fe～Al／Cr3C2RE复合涂层在650℃时的涂盐抗热腐蚀性能明显优于基体20钢及同类型的复合涂层。Cr元素及稀土氧化物是Fe—Al／Cr3C2RE复合涂层性能优异的主要原因。     

电弧喷涂技术及其在火电厂中的应用

阐述了电弧喷涂技术的原理和特点。针对火力发电厂锅炉水冷壁的热腐蚀问题,自行开发了SL30专用丝材。通过该材料和其他几种材料电弧喷涂涂层的耐热腐蚀性能对比试验,证明了SL30材料制备的涂层具有优良的性能价格比。介绍了电弧喷涂SL30丝材在几个火力发电厂锅炉水冷壁上的大面积应用情况。     

锅炉受热面复合陶瓷涂层抗高温腐蚀性能试验研究

对一种新型的复合陶瓷涂层进行抗高温腐蚀性能研究,以电站锅炉水冷壁材料20G钢为基材,将该涂层涂覆于20G钢表面,进行试验。将试验对象分为喷涂涂层的试样片和未喷涂的对比钢材样片,对两种样片在450℃温度下进行模拟SO2气氛、H2S气氛以及熔盐腐蚀3种情况的高温腐蚀试验研究。研究发现:喷涂涂层的试样片抗SO2、H2S腐蚀效果明显优于未喷涂涂层的20G钢,分别增强约6倍和10倍;进行高温熔盐腐蚀,喷涂涂层的试样片抗腐蚀能力约为未喷涂的20G钢的2倍。     

锅炉受热面管的复合涂层防护的研究

针对燃煤电站锅炉因受热面管子磨蚀严重,导致泄漏、爆管等而被迫停炉检修的情况,开展了受热面管复合涂层防护技术的研究。根据受热面管的形状、工况条件和使用环境,对电弧喷涂工艺进行了探讨,并对若干适用于锅炉抗高温磨蚀的喷涂丝材所制成涂层的微观组织结构、硬度、涂层结合性能、耐冲蚀磨损性能和抗高温腐蚀性能等进行了深入的分析。结论是以超音速电弧喷涂NiAl丝材作为结合底层,金属-陶瓷材料或高铬材料作为功能层并辅以高温封孔的复合涂层的制备技术,可以同时兼顾可靠性和经济性。     

高速电弧喷涂Fe-Al/Cr3C2RE复合涂层抗高温腐蚀性能探讨

使用Fe-Al/Cr₃C₂RE粉芯喷涂丝材,结合高速电弧喷涂技术（HVAS）在20钢上制备Fe-Al/Cr₃C₂RE复合涂层,同时以Fe-Al/Cr₃C₂涂层为比较。通过对涂层进行650℃下涂盐热腐蚀试验,借助扫描电镜观测腐蚀前后涂层表面形貌,利用XRD确定涂层的相组成,对腐蚀后涂层截面进行EDS分析。结果表明:Fe-Al/Cr₃C₂RE复合涂层在650℃时的涂盐抗热腐蚀性能明显优于基体20钢及同类型的复合涂层。Cr元素及稀土氧化物是Fe-Al/Cr₃C₂RE复合涂层性能优异的主要原因。     

电弧喷涂技术及其在火电厂的应用研究

阐述了电弧喷涂技术的原理和特点，针对火力发电感和锅炉水冷壁热蚀问题，自行开发了ＳＬ３Ｏ专用丝材。通过该材料和其他几种材料电弧涂涂层的耐热腐蚀性能对比试验，证明了ＳＬ３Ｏ材料制备的涂层具有优异的性能价格比，适于在我国大范围内使用。此外，还介绍了电弧     

热喷涂工艺在电器产品表面防腐中的应用

介绍了丝材火焰喷涂和丝材电弧喷涂工艺的基本原理和使用的主要设备，以及热喷锌的工艺要求及其技术优势。     

喷涂距离对感应耦合等离子体喷涂B4C/W涂层 结合强度的影响

B_4C材料可用作原位保护涂层防止托卡马克面向等离子体部件中的钨块受到诸如腐蚀、开裂以及颗粒溅射等损伤。本文采用感应耦合等离子体(ICP)喷涂法在惰性气氛下制备B_4C/W涂层,对不同喷涂距离下的涂层进行结合力研究,并对其表面形貌进行分析,同时还对涂层的物相及组成成分进行了分析。不同喷涂距离下的拉伸测试结果展示了涂层结合强度的变化趋势,结果表明,在喷涂距离比较近时涂层的结合强度反而较弱。优化条件下的涂层结合强度值为5.32MPa。涂层表面形貌的SEM图像分析,进一步验证了结合强度的研究结果。与初始B_4C粉末相比,涂层的主要相成分和化学成分没有发生改变。     

锅炉"四管"防腐耐磨涂层性能研究

对锅炉“四管”常用的3种超音速电弧喷涂涂层进行了高温腐蚀和冲蚀性能试验,对涂层的组织结构、结合强度、显微硬度进行分析,获得了各种喷涂层的综合性能.结论可为火电厂锅炉“四管”的高温防腐耐磨提供技术依据.     

超音速火焰喷涂在电力系统中的应用研究

内蒙古电力科学研究院采用超音速火焰喷涂技术（HVOF）,首次对Fe—Al／Cr3C2金属间化合物复合涂层进行试验研究。不仅解决了Fe—Al合金难以加工成形的难题,又使Cr3C2含量任意调配,突破了粉芯丝材由于包覆率问题而使得增强相含量受到局限的瓶颈。通过正交试验,成功得出Fe-Al／Cr,C2复合涂层性能最优时的化学成分配比。     

超音速活性电弧喷涂技术在接地网腐蚀防护中的应用

在分析接地网腐蚀机理的基础上,提出利用超音速活性电弧喷涂新技术制备导电防腐涂层来解决目前接地网材料耐蚀性能差的问题。分析了超音速活性电弧喷涂新技术的工作原理及其应用于接地网防腐的可行性,并特别提出未来接地网导电防腐涂层的设计思路。     

等离子喷涂的陶瓷涂层的特性

测量分析了三种等离子喷涂的陶瓷涂层 (Al2 O3 、Cr2 O3 、Cr3 C2 +NiCr)的显微组织、孔隙率、显微硬度及结合强度等性能 ,并通过吹砂试验对三种涂层的抗磨损性能进行了比较。结果表明 ,在抗冲蚀磨损方面 ,Cr2 O3 陶瓷涂层优于Al2 O3 及Cr3 C2 +NiCr涂层。     

管内约束碳化钨粉末电爆喷涂涂层的特性

为实现用碳化钨粉末作为喷涂材料制备电爆喷涂涂层,开发了一种连续送粉的管内约束电爆喷涂方法,试验研究了初始电压及喷涂距离对涂层特性的影响。结果表明:在一定的喷涂距离范围内,这种方法可以使碳化钨颗粒全部以熔融状态形成液相涂层,这类涂层致密度较高,与基体有较高的结合强度,当喷涂距离很小时,如1mm,涂层表面呈现气相沉积的特征。随着喷涂距离的增大,爆炸产物中部分熔融粒子开始凝固成固相颗粒,形成含有固相颗粒的涂层,这种涂层的致密度下降,与基体结合强度较低。随着初始电压的升高,获得液相涂层和含有固相颗粒的涂层的喷涂范围增大。     

SOFC用Ni/Al_2O_3金属陶瓷支撑层组织结构与气密性

采用氧乙炔火焰喷涂方法制备了含量不同的聚苯酯为造孔剂(PPHBA)的NiO/Al_2O_3涂层,系统地研究了造孔剂含量对涂层组织结构和气体渗透率的影响.研究结果表明,造孔剂的添加量对涂层的组织结构有显著影响,粉末中不添加造孔剂时,涂层的孔隙较少且分布均匀;涂层中添加造孔剂后,大气孔数量显著增多,且随着粉末中添加造孔剂含量的增加而增大.NiO/Al_2O_3涂层经高温还原处理后的渗透率显著高于喷涂态涂层渗透率,且气体渗透率随着喷涂粉末中造孔剂含量增加而增大.NiO还原处理后涂层的气体渗透率比喷涂态提高约一个数量级.     

Research on the interfacial reaction between amine group in urea and the coating materials of polyurethane coated urea

Abstract

In this work, the polyurethane coated urea (PCU) and PE coated urea (PECU) were prepared by spraying the coating material. The isocyanates coatings on the surface of urea and granule inorganic compound fertilizer (NPK) were prepared and their infrared spectra were compared. The polyurethane coatings of PCU was analyzed by IR. The interface morphology between the PU coating and PE coating PECU and the surface of urea was compared by scanning electron microscope. The inner and outer surfaces morphology of polyurethane coatings was studied. The results showed that the peak of -NCO groups in the infrared spectrum of the coating on urea was weaker than of the coating on NPK, while the peaks of N-H, C-N and C?=?O were all relatively stronger, which proved that -NH₂ in urea reacted with -NCO during the coating formation. SEM images showed that there was an obvious gap between PE coating and its urea core, while PU coating was tightly bonded with the surface of urea core, and the inner surface of PU coating had something undissolved after fully dissolved in water, which further illustrated that urea participate in the reaction of isocyanates with polyols. All of this results demonstrated that the amine group (-NH₂) in urea reacted with the -NCO group in isocyanates and urea linkage (-NH-CO-NH-) was formed in the polyurethane coating.     

超音速火焰喷涂WC/Co涂层的组织性能研究

采用超音速火焰喷涂工艺在TP347不锈钢基体上制备了厚度达180μm的WC/Co涂层。采用金相显微镜、X射线衍射仪对涂层的组织及相组成进行了研究,用显微硬度计和WE-10A试验机对涂层的显微硬度和结合强度进行了测试。结果表明,涂层物相主要由3种组成,分别为WC、W2C、Co3WC。该涂层显微硬度最大达1137HV0.1/20,结合强度可达63.7 MPa。     

超音速火焰喷涂制备CrC-NiCr耐磨涂层试验研究

利用超音速火焰(HVOF)喷涂技术在St T16/25Mo合金表面成功制备了Cr3C2-NiCr耐磨涂层,获得了制备Cr3C2-NiCr耐磨涂层的工艺参数。结果表明:Cr3C2-NiCr涂层致密、孔隙率很低、显微硬度和结合强度较高,具有优异的耐高温、耐磨、耐蚀和抗氧化性能,涂层厚度等各项指标均符合技术文件的要求;采用的HVOF喷涂工艺参数合理,Cr3C2-NiCr涂层可应用于阀杆、阀头和导套等关键零部件的生产中。     

Choice and optimization of ratio of components to develop fast-mounted thermostable heat-insulating constructions

Fast-mounted heat-insulating constructions based on foamed synthetic rubbers, polyethylene, and polyurethane are characterized by a thermostability up to 150°C and emit toxic substances when burnt. However, there is a need for heat insulation of surfaces with higher coolant temperatures, such as pipelines, equipment of nuclear and thermal power plants, and heating systems with remote heat sources. One of the most promising types of heat insulation materials for creation of fast-mounted heat insulation constructions is the syntactic foams or thin-film multilayer heat-insulating coatings (TFMHIC), which are created using hollow microspheres and various types of binders. The formation of TFMHIC on the heat-insulating surface is carried out mostly by means of spraying methods that have well proven themselves at coating on flat and cylindrical surfaces of large area, but they turned out ineffective for cylindrical surfaces with a diameter of 300 mm and less, since they are characterized by a large degree of carryover of composite material. This article analyzed the binders and microspheres promising to create the fast-mounted heat-insulating constructions based on TFMHIC with high thermostability. Based on the analysis, a conclusion is drawn that organicsilicon binding and glass microspheres are promising for use in the heat-insulating constructions with thermostability up to 300°C. The results of experimental research are given that point to the possibility of predicting the optimal composition of heat-insulating material characterized by a high degree of filling with microspheres with maintaining the mechanical strength, by means of performing the analysis of rheological characteristics of nonpolymerized liquid compositions of heat-insulation material. The index of tensile strength in bending was the criterion for evaluating the mechanical strength of heat-insulating material. The critical volume concentrations of filling the heat-insulating material with glass microspheres, whose excess leads to a reduction in its strength characteristics, are determined.     

电站锅炉受热面涂层抗高温氧化性能的研究

针对电站锅炉受热面因高温氧化而导致的爆漏,采用Q235低碳钢作为基体,分别喷涂PS45、FeCrAl、4Cr13等3种涂层,与没有涂层保护的钢研102钢管材进行抗高温氧化试验。结果表明,没有涂层保护的钢研102钢抗氧化能力较差,而Q235低碳钢经电弧喷涂保护后其抗氧化性能得到大幅度的提高。其中,PS45涂层中由于Cr、Ni含量较高,在试样表面可持续形成结构致密、性质稳定的Cr2O3保护层,具有优异的抗氧化性能,使试样得到充分保护。