氧化锌对醇溶性无机富锌漆性能的影响

研究了醇溶性无机富锌漆中球状锌粉被氧化锌粉取代对涂层性能的影响.通过电位-时间曲线研究了涂层在3.5％NaCl溶液中电化学活性的变化情况,同时记录了涂层的耐盐水时间,耐盐雾时间.结果显示:随氧化锌的增加涂层的耐盐水和耐盐雾时间均都是先延长后缩短,在w(氧化锌)为15％时达到最大值.涂层的阴极保护时间呈现同样的规律.     

片状锌粉对醇溶性无机富锌涂层性能的影响

在颜料总吸油量一定、各配方中颜料体积浓度(PVC)与临界颜料体积浓度(CPVC)之比为0.77的条件下,通过盐雾试验、极化曲线、开路电位(OCP)-时间曲线和电化学阻抗谱(EIS)研究了片状锌粉取代醇溶性无机富锌涂料中少量球状锌粉对涂层性能的影响.研究结果表明,在片状锌粉取代比为5％ ～ 30％范围内,涂层的耐盐水和耐盐雾腐蚀时间随片状锌粉取代比的增加而先增加后减少,在取代比为20％时达到最大值.与未取代涂层相比,取代比为20％的涂层其牺牲阳极保护时间更长,阳极溶解性能更好,低频(0.2 Hz)阻抗更小.     

4种粉体对醇溶性无机富锌漆耐蚀性能的影响

研究了石墨、磷铁粉、滑石粉和高钛灰取代醇溶性无机富锌漆中的部分球状锌粉对涂层耐蚀性的影响。通过耐盐水、耐盐雾以及开路电位–时间测试,研究了涂层的耐蚀性。结果表明,各粉体取代涂层都有一个最优取代比,且在最优取代比时涂层的阴极保护时间最长。导电粉取代涂层比非导电粉取代涂层的防腐效果更好。导电粉取代涂层的初始开路电位随取代比的增大先负移后正移,在最优取代比时达到最负值;非导电粉取代涂层的初始开路电位随着取代比的增大而逐渐正移。     

改性环氧富锌底粉在高耐盐雾锈蚀方面的研究

防腐型熔结环氧粉末涂料与富锌环氧粉末涂料应用多年,但在很多高耐盐雾锈蚀环境仍无法完全替代溶剂型涂层.为提升粉末涂料耐盐雾性能,本研究通过对环氧富锌粉末涂料进行改性,在降低涂层体积电阻率的基础上提升牺牲阳极效率,使涂层达到液体涂料耐盐雾等级性能.结果 表明:添加0.2％导电材料单壁碳纳米管与30％片状锌粉以及其他功能助剂...     

快干型环氧固化剂在水性环氧底漆中的应用

对比了自制的快干型固化剂STW703K与市售固化剂在水性环氧底漆中的应用性能.对其常规的机械性能、耐盐雾性能、耐3％NaCl水溶液、耐50℃热水性能和耐碱性能进行了研究,发现这两种快干型固化剂制备的漆膜表干速度快、机械性能良好、耐盐水和耐热水性能佳.而自制快干型固化剂制备的漆膜耐盐雾性和耐碱性能更好.     

高性能水性环氧富锌底漆的研制

以自制的改性环氧树脂和水性胺类固化剂为基料,加入锌粉防锈颜料和助剂,研制了一种水性环氧富锌底漆,并对涂层的耐盐雾性、耐盐水性和机械性能进行了测试。结果表明：锌粉的添加量在75％～80％时,漆膜的防腐蚀性能最好;1％有机膨润土与0．5％气相二氧化硅配用,可有效解决水性环氧富锌底漆中锌粉沉降、结块的问题。     

油井管国产临时性防护涂料的试验研究

从成本分析、政策分析、性能分析(包括物理性能、耐盐雾试验、耐5%盐水浸泡试验、油溶性试验等)进行了2种涂料的对比,证明了国内产品在防腐蚀性能、脱除性等临时性防护涂层所需的功能上完全可以取代进口产品。并且在保证性能质量的前提下,国产产品具有更强的价格优势,因而该产品可实现进口替代。     

锌铝合金涂层与有机涂层的耐盐雾腐蚀性能对比研究

研究了锌铝合金涂层与有机涂层的耐盐雾性能,在防腐涂层体系中,锌铝合金涂层的耐盐雾防腐性能好于有机涂层;而在防腐防污涂层体系中由于防污漆含有铜,锌铝涂层与铜离子可形成原电池加速腐蚀,锌铝合金涂层的防腐性能差于有机涂层体系。     

氟碳涂层体系对混凝土防护效果的研究

通过附着力、耐碱性、耐盐雾、透气性和吸水率试验比较了溶剂型和水性氟碳涂层的防腐效果,研究表明:溶剂型和水性氟碳涂层均具有良好的附着力、耐碱性和耐盐雾性能,溶剂型氟碳涂层能够完全封闭混凝土的孔隙,水性氟碳涂层的吸水率较大。     

无铬达克罗工艺的研究

以有机树脂代替铬酐,在无铬达克罗工艺研究中进行正交试验.从盐雾试验中得出影响无铬达克罗涂层的因素,由大到小依次是:水、增稠荆、固化剂、树脂.用最佳配方制得的涂层与舍铬达克罗涂层进行对比,无铬达克罗涂层的外观比含铬达克罗略差.附着力、机械性能略优,双层耐盐雾时间与含铬达克罗的接近.     

The corrosion resistance of 316L stainless steel coated with a silane hybrid nanocomposite coating

The present work aims at evaluating the corrosion resistance of 316L stainless steel pre-treated with an organic–inorganic silane hybrid coating. The latter was prepared via a sol–gel process using 3-glycidoxypropyl-trimethoxysilane as a precursor and bisphenol A as a cross-linking agent. The corrosion resistance of the pre-treated substrates was evaluated by neutral salt spray tests, linear sweep voltammetry and electrochemical impedance spectroscopy techniques during immersion in a 3.5% NaCl solution. In addition, the effect of the drying method as an effective parameter on the microscopic features of the hybrid coatings was studied using Fourier transform infrared spectroscopy and scanning electron microscopy. Results show that the silane hybrid coatings provide a good coverage and an additional corrosion protection of the 316L substrate.     

铝合金表面钛酸盐化学转化膜研究

基于含铬处理对环境影响的考虑,世界范围内都在积极开发有效的替代技术,用于铝合金腐蚀保护从而代替铬酸盐转化处理。研究了铝合金钛酸盐处理技术。通过循环极化曲线和盐雾试验测定,钛酸盐和铬酸盐化学转化膜都有非常宽的钝化区,在NaC l(c=0.5 mol/L)溶液中2种氧化转化膜均没有击穿电位;钛酸盐转化处理的样品经336 h盐雾试验表面无点腐蚀发生。钛酸盐转化膜可以为铝合金提供良好的腐蚀保护作用。     

Mercapto functional azole compounds as organic corrosion inhibitors in a polyester-melamine coating

The corrosion inhibition of two mercapto functional azole compounds including 2-mercaptobenzimidazole (MBI) and 2-mercaptobenzoxazole (MBO) for mild steel in 1 M NaCl solution was studied by electrochemical impedance spectroscopy (EIS), then their impact on the protective performance of a polyester-melamine coating was evaluated using salt spray. EIS results revealed a higher corrosion inhibitive activity of MBI compared to that of MBO. Corrosion products were examined by SEM-EDX and FTIR. The results showed modification of the corrosion products in the presence of MBI and MBO. The salt spray results revealed an improved corrosion protection of the coatings formulated with MBI and MBO. There was almost no impact of MBI and MBO on adhesion strength and glass transition temperature of the coatings, meaning that their impact on the corrosion protection performance of the formulated coating could only be attributed to their effect on the corrosion products.     

Studying the corrosion protection properties of an epoxy coating containing different mixtures of strontium aluminum polyphosphate (SAPP) and zinc aluminum phosphate (ZPA) pigments

Epoxy/polyamide coatings were loaded with different mixtures of strontium aluminum polyphosphate (SAPP) and zinc aluminum phosphate (ZPA) pigments. Moreover, a coating containing zinc phosphate (ZP) was prepared as a reference sample. The coatings were applied on St-37 steel substrates and then were exposed to 3.5 wt% NaCl solution up to 35 days. The corrosion inhibition properties of the pigments extracts were studied on bare steel samples by a potentiodynamic polarization technique after 24 h immersion. The morphological properties and corrosion resistance of the coatings were investigated by scanning electron microscope (SEM), optical microscope, electrochemical impedance spectroscopy (EIS) and salt spray tests.     

The corrosion resistance of 316L stainless steel coated with a silane hybrid nanocomposite coating

The present work aims at evaluating the corrosion resistance of 316L stainless steel pre-treated with an organic–inorganic silane hybrid coating. The latter was prepared via a sol–gel process using 3-glycidoxypropyl-trimethoxysilane as a precursor and bisphenol A as a cross-linking agent. The corrosion resistance of the pre-treated substrates was evaluated by neutral salt spray tests, linear sweep voltammetry and electrochemical impedance spectroscopy techniques during immersion in a 3.5% NaCl solution. In addition, the effect of the drying method as an effective parameter on the microscopic features of the hybrid coatings was studied using Fourier transform infrared spectroscopy and scanning electron microscopy. Results show that the silane hybrid coatings provide a good coverage and an additional corrosion protection of the 316L substrate.     

The lifetime assessment of low infrared emissivity composite coatings in chloride environments

The microstructural-electrochemical model is employed to predict the lifetime of low infrared emissivity composite coatings in chloride environments. Electrochemical data collected in 3.5 wt.% NaCl solution is presented for the low infrared emissivity coating, and these values are used as inputs for a mechanistic-based corrosion model which yields the salt spray life of the coating. To check the calculated results, the model predictions were compared with the results of salt spray tests. The current work showed that the model was able to predict lifetime of low infrared emissivity coating under salt spray, but tended to under-predict lifetime at short times and over-predict at long times. Under-prediction may be associated with corrosion protection of metallic pigment particles by polymer. Over-prediction by the model at longer exposure times may be associated with the fact that an influence of porosity is not included as a part of this simple model.     

The lifetime assessment of low infrared emissivity composite coatings in chloride environments

The microstructural-electrochemical model is employed to predict the lifetime of low infrared emissivity composite coatings in chloride environments. Electrochemical data collected in 3.5 wt.% NaCl solution is presented for the low infrared emissivity coating, and these values are used as inputs for a mechanistic-based corrosion model which yields the salt spray life of the coating. To check the calculated results, the model predictions were compared with the results of salt spray tests. The current work showed that the model was able to predict lifetime of low infrared emissivity coating under salt spray, but tended to under-predict lifetime at short times and over-predict at long times. Under-prediction may be associated with corrosion protection of metallic pigment particles by polymer. Over-prediction by the model at longer exposure times may be associated with the fact that an influence of porosity is not included as a part of this simple model.     

High corrosion resistance of electroless composite plating coatings on AZ91D magnesium alloys

The process of electroless plating Ni-P on AZ91D magnesium alloys was improved. The Ni-P-ZrO₂ composite coatings and multilayer coatings were investigated based on the new electroless plating process. The coatings surface and cross-section morphologies were observed with scanning electron microscopy (SEM). The chemical compositions were analyzed by EDXS. The corrosion behaviors were evaluated by immersion, salt spray and electrochemical tests. The experimental results indicated that the Ni-P-ZrO₂ composite coatings suffered attack in NaCl solution but displayed passivation characteristics in NaOH and Na₂SO₄ solutions. The corrosion resistance of Ni-P-ZrO₂ coatings was superior to Ni-P coatings due to the effect of ZrO₂ nano-particle. The multilayer coatings consisting of Ni-P-ZrO₂/electroplating nickel/Ni-P (from substrate to surface) can protect magnesium alloys from corroding more than 1000 h for the salt spray test.     

Corrosion protection coating containing polyaniline glass flake composite for steel

Corrosion protection of steel by glass flake (GF) containing coatings is widely used in marine atmosphere. Even though, the coatings containing glass flake are highly corrosion resistant, their performance is decreased due to the presence of pinholes and coating defects. It is well established that polyaniline containing coating is able to protect the pinhole defects in the coatings due to passivating ability of polyaniline. Hence a study has been made on the corrosion protection ability of steel using polyaniline-glass flake composite containing coating with 10% loading of glass flake in epoxy binder. The polyaniline glass flake composite (PGFC) was synthesized by chemical oxidation of aniline by ammonium persulphate in presence of glass flake. The corrosion protection ability of GF and PGFC containing coating on steel was found out by salt spray test and EIS test in 3% NaCl. In both the tests, the resistance value of the PGFC containing coating has remained at 10⁸-10⁹ Ω cm² where as for the GF containing coating, the resistance values decreased to 10⁵ Ω cm². The enhanced corrosion protection ability of the PGFC containing coating is due to the passivation ability of the polyaniline present in the coating.     

Assessment of hydrophobic and anticorrosion properties of composite silane–zeolite coatings on aluminum substrate

The effect of matrix compounds on the behavior of silane–zeolite composite coatings on a 6061 aluminum alloy was evaluated by electrochemical test performed at long immersion time in 3.5% NaCl solution. It was observed that silane chains influence the hydrophobic behavior and the electrochemical performances of the zeolite-based composite coating. All composite coatings showed a long-term protection action in 3.5% NaCl solution. The use of silane compounds with long alkyl chain or with bi-hydroxyl groups made it possible to obtain electrochemically stable coating during long immersion time. Best results have been obtained with a multicomponent silane mixture (short and long molecular chains).