铜基表面陶瓷涂层的制备与耐蚀性能研究

以Al2O3、TiO2和ZnO为骨料,钠水玻璃为粘接剂,在纯铜表面用热化学反应法制备了陶瓷涂层。X射线分析发现,陶瓷涂层热固化后,涂层内产生了NiAl2O4、Al2SiO5等新相,它提高了涂层与基体的结合强度。腐蚀实验表明,封孔后陶瓷涂层的耐酸、耐碱、耐盐等性能分别比纯铜基体提高了3.9、12.3和6.3倍;极化曲线表明,陶瓷涂层有明显的钝化区,其抗电化学腐蚀能力增强,抗盐雾腐蚀性比基体提高了5.0倍。     

镁合金表面纳米Al2O3陶瓷涂层的制备及耐磨性研究

采用热化学反应法在MB2镁合金表面制备了含有纳米Al2O3粒子的陶瓷涂层。采用XRD分析了微米Al2O3陶瓷涂层和纳米Al2O3陶瓷涂层的相结构,并测试了这两种涂层的耐磨性及耐热冲击性。结果表明,微米级Al2O3陶瓷涂层磨粒磨损及黏着磨损耐磨性相对于镁合金基体分别提高了14%及47%,且涂层中有新相MgMnSiO4生成;纳米Al2O3陶瓷涂层耐磨性及耐热冲击性优于以微米粒子制备的陶瓷涂层,磨粒磨损及黏着磨损耐磨性相对于基体分别提高了55%及100%,涂层中产生新相Mg2SiO4和Al2SiO5。     

管道等离子喷涂Cr_2O_3复合涂层及其耐蚀性能

采用等离子喷涂技术在X70管线钢表面喷涂Cr_2O_3复合涂层,利用X射线衍射仪、扫描电镜、维氏硬度计、划痕仪、电化学工作站等方法表征了涂层相关特征与性能。结果表明,相成分主要是Cr_2O_3和TiO_2,硬度可达4.928GPa,结合力可达46.15N,粘结层+陶瓷层试样腐蚀速率显著降低,对基体有很好的耐蚀保护作用。     

放热体系对粉煤灰玻璃/陶瓷复合涂层耐蚀性的影响

以粉煤灰及少量SiO2、Al2O3、MgO和钠长石为主要原料,采用热化学反应法在Q235钢基体上制备了玻璃/陶瓷复合涂层.在此基础上添加10％的Al-TiO2-B2O3体系,通过对涂层形貌、物相、抗热震性、孔隙率及耐蚀性测试研究放热体系对复合涂层组织和性能的影响.实验结果表明:Al-TiO2-B2O3放热体系的加入可以促进热化学反应生成更多的新相,同时低熔点的Al粉可以优先熔化,填充涂层的孔隙和裂纹,利于提高复合涂层的性能.     

氧化钙对煤矸石粉末陶瓷涂层耐蚀性的影响

本文采用含多种氧化物的煤矸石粉末,以加钙活化的煤矸石和未加钙的煤矸石两种配方为涂层骨料,用热化学反应法在Q235钢表面制备陶瓷涂层.通过XRD分析球磨前后粉体及陶瓷涂层的相结构,并分析涂层的抗热震性和耐蚀性能.结果表明,通过热化学反应法制备煤矸石陶瓷涂层是可行的,制备过程中产生Al6Si2O13、Al2 SiO5、AINi、CaAl2 Si2O8及玻璃新相.涂层的性能比基体有了很大的提高,其中煤矸石陶瓷涂层的耐酸、碱、盐性分别提高4.31倍、2.08倍、2.06倍;加钙煤矸石陶瓷涂层分别提高9.79倍、2.38倍、2.86倍.     

Al_2O_3—SiO_2混合溶胶—凝胶涂层对工程陶瓷表面改性的研究

利用溶胶—凝胶法在SG4工程陶瓷基体上成功制备了Al2 O3—SiO2 混合涂层 ;通过X射线仪测定了Al2 O3—SiO2 凝胶粉末的晶相组成。对精磨、热处理、Al2 O3涂层和Al2 O3—SiO2 混合涂层四种试样抗弯强度的样本均值和样本标准离差进行了比较 ,并通过观察四种试样表面的SEM形貌和两种涂层试样断面的SEM形貌初步分析了表面改性的原因。分析结果表明 :溶胶涂层对基体表面微裂纹有一定的弥合作用 ,可以提高基体的抗弯强度而降低材料强度的分散性 ,其效果好于单纯的热处理 ,Al2 O3—SiO2 混合涂层试样的表面质量优于Al2 O3涂层试样 ;Al2 O3—SiO2 混合涂层渗入基体更深 ,可以更好地弥合基体表面微裂纹 ,有效提高基体的抗弯强度。     

高熔点复合氧化物陶瓷的相可控低温烧成

提出以玻璃陶瓷的母体玻璃作为烧结助剂,低温液相烧结复合氧化物陶瓷的技术思路。研究了BaO–Al2O3–SiO2(BAS)玻璃的高温黏流特性和降温析晶特性,以确定其液相烧结工艺。以BAS玻璃作为烧结助剂,由液相烧结制备了Y2Si2O7,Y2SiO5,3Al2O3·2SiO2或La2Zr2O7复合氧化物陶瓷。结果表明:采用钡长石玻璃陶瓷的母体玻璃作为烧结助剂,可实现高熔点复合氧化物陶瓷的低温烧成,能制备以设计的复合氧化物为主晶相,母体玻璃析晶得到钡长石为次晶相的复合氧化物陶瓷。     

镁合金固相反应复相陶瓷涂层性能对比

采用固相反应法分别在MB2镁合金基体上制备Al2O3基和SiO2基复相陶瓷涂层,确定了陶瓷涂层的较佳配方如下:SiO2基陶瓷涂层为m(SiO2):m(Al2O3):m(MgO):m(钠长石)=66.8:13.2:12:8,Al2O3基陶瓷涂层为m(Al2O3):m(SiO2):m(MgO):m(ZnO)=66:12:12:10,陶瓷料浆与粘接剂质量比为0.5:1。对所制备的涂层结构,封孔前后涂层的致密性、耐酸性、耐盐水性以及耐磨性进行了测试。结果表明,SiO2基复相陶瓷涂层因在热固化过程中产生大量新相,而提高了涂层的致密性。与镁合金基体相比,封孔后涂层的耐酸性和耐盐水性分别提高了21倍和17倍,相对耐磨性增强了1.94倍,均优于封孔后Al2O3基复相陶瓷涂层的相关性能。     

溶胶-凝胶法制备不锈钢表面SiO2-TiO2-Al2O3-ZrO2涂层

在乙醇中,分别以盐酸、醋酸为催化剂,以正硅酸乙酯、钛酸正丁酯、硝酸铝、氧氯化锆为金属醇盐前躯体,通过分步水解法制备了SiO2-TiO2-Al2O3-ZrO2复合溶胶,利用浸渍法将陈化后的复合溶胶涂覆到不锈钢表面制得透明的复合涂层。对SiO2-TiO2-Al2O3-ZrO2复合涂层进行了差热分析(DTA)、失重分析(TG)、红外光谱(IR)、X射线衍射分析(XRD)以及耐HCl、CuSO4和FeCl3溶液浸泡腐蚀实验。结果表明,涂层中存在TiO、SiO、AlO键的氧化物网状结构,其XRD图中出现了锐钛矿和板钛矿的相结构。该涂层致密,具有良好的耐蚀性能。     

Q235钢热化学反应法制备玻璃质陶瓷涂层的研究

采用热化学反应法,以MgO–SiO2、MgO–Al2O3为基料,分别添加6种低熔点玻璃粉,在Q235钢表面制备不同玻璃质陶瓷涂层。研究了各种涂层的热固化状况。结果发现,以MgO–SiO2为基料的G3、G4和G5涂层有良好的外观。耐蚀、耐磨和抗热震性实验表明,以m(MgO)∶m(SiO2)∶m(5#玻璃粉)=9∶9∶2为基料的G5涂层其性能最佳。XRD谱图和SEM照片显示,G5涂层生成了新的陶瓷相,从而增强了基体和涂层的结合力。     

An ASTM Standard for Quantitative Scratch Adhesion Testing of Thin, Hard Ceramic Coatings

Thin, hard ceramic coatings on metals and ceramics are extensively used for wear and abrasion resistance, friction control, corrosion resistance, and tailored functional (electrical, optical, and magnetic) properties across a wide range of high-performance applications. Coating producers and users have to measure and control the coating-substrate adhesion strength, because adhesion failure is often the primary failure mechanism of the coating, limiting its performance and life. The quantitative test method of choice for thin hard coatings is scratch adhesion testing. In this technique, a diamond stylus is drawn across the coating on the surface under increasing normal load and the damage to the coating is assessed against the applied load. With DOE funding and in coordination with the ASTM Committees C28, G08, and B02, a new scratch adhesion test standard has been researched and written and has been published. The ASTM C1624 test standard (Adhesion Strength and Mechanical Failure Modes of Ceramic Coatings by Quantitative Scratch Testing) provides comprehensive and detailed guidance and instructions on scratch adhesion testing of thin, hard ceramic coatings—the principles, terminology, applications, limitations, equipment, specimen preparation and characterization, critical experimental factors, calibration, procedures, calculations, and reporting requirements.     

金属表面Ni/Al-13wt%TiO2/Al2O3梯度复合陶瓷涂层的腐蚀行为

为了解决陶瓷涂层中的通孔问题，把复合材料与梯度材料的主应用到陶瓷涂层，采用等离子喷涂技术在Q235钢表面形成Ni/Al-13wt％TiO2/Al2O3梯度复合陶瓷涂层，对其在沸腾的5％HCl溶液中的腐蚀行为进行了研究。结果表明，Ni/Al-13wt%TiO2/Al2O3梯度复合陶瓷涂层中的通孔率较单一层Al2O3陶瓷涂层显著降低，带有该梯度复合陶瓷涂层试样的耐蚀性明显提高，该涂层腐蚀14天仍未出现鼓泡削落现象。     

硅酸盐矿物/TiB2复相陶瓷涂层的制备及耐蚀性能研究

本文采用热化学反应法在Q235钢基体表面分别制备了硅酸盐矿物陶瓷涂层和添加Al-TiO2-B2O3反应体系复相陶瓷涂层,用XRD分析其相结构,并研究了涂层的耐蚀性。结果表明,硅酸盐矿物/TiB2复相陶瓷涂层有TiB2、FeNi3、CaNi0.5Si1.5等新相产生。耐酸、碱、盐性相对基体分别提高8.6倍,4.4倍,6.2倍,耐蚀性优于纯硅酸盐矿物涂层。     

陶瓷涂层结构优化及失效机理的研究现状

陶瓷涂层以其优异的耐磨损、耐高温、耐腐蚀等性能表现出巨大的工程应用前景。但是,在服役过程中因温度变化和受力诱发的裂纹产生、扩展,甚至导致涂层开裂、剥落及失效,这些因素限制了涂层的应用,因此通过结构优化改善陶瓷涂层的抗开裂、剥落性能较为重要。本文首先论述了纳米结构涂层、耐磨多层涂层、复合涂层的失效机理及其结构优化。提出了利用单次喷涂制备粘结层和陶瓷层的方法,通过该方法可以消除陶瓷层与粘结层间的界面形态,提高涂层的断裂韧性、粘结强度。最后展望了陶瓷涂层在材料组分设计和工艺优化研究中应重点关注的方面。     

金属基表面Al2O3-SiO2涂层耐腐蚀性能的研究

由溶胶完全混合后再制备的Al2O3-SiO2复合涂层在碱性、酸性介质中都表现出更好的耐腐蚀性.     

金属基耐高温陶瓷涂层抗热冲击性能的研究

为提高金属基陶瓷涂层的抗热冲击性能，以无机胶粘剂磷酸二氢铝、耐磨陶瓷骨料氧化铝、碳化硅和氧化镁混合后涂覆于金属表面制得陶瓷涂层。通过交替加热及冷却试验测试该陶瓷涂层的抗热冲击性能，并与其他人的研究数据进行比较。所得涂层抗热冲击次数超过10次，超过了其他人的实验数据，这是由于涂层与基体在界面处相互扩散形成过渡层。另外，宏观上的机械联锁有利于提高涂层与基体在界面处的结合，从而提高了其抗热冲击性能。     

Structural characterization and adhesion appraisal of TiN and TiCN coatings deposited by CAE-PVD technique on a new carbide composite cutting tool

A new composite matrix was developed for a cutting tool based on tungsten carbide ligated with cobalt (WC-Co) using sintering technique. The admixtures of niobium carbide, tantalum carbide, and titanium carbide with the WC-Co matrix aim to inhibit the grain growth of WC and to promote covalent bonding at the interface. The modified WC-Co tools were coated with titanium nitride and titanium carbonitride layers by CAE-PVD technique. To substantiate the performances of the new coating-substrate systems, we have performed X-ray diffraction, atomic force microscopy, and scratch test measurements to estimate: phase content, average crystallite size, average texture coefficient, residual stress level, coating thickness, average roughness, square mean root, fractal dimension, cohesive adhesion, and adhesive adhesion. The results enable the in-depth understanding of the coating growth mechanisms and provide an objective evaluation of the coatings adhesion to the new cutting tools matrix. The results provide evidence to support the potential of TiN and TiCN coatings to enhance the working performances of the composite WC-Co cutting tools and to differentiate their properties. TiCN coating is shown to be superior to TiN coating in terms of adhesion and thus represents a better alternative for coating the modified WC-Co composite matrix.     

Effects of electrophoretic deposition times and nanotubular oxide surfaces on properties of the nanohydroxyapatite/nanocopper coating on the Ti13Zr13Nb alloy

Load-bearing implants are developed with a particular emphasis placed on an application of ceramic hydroxyapatite coatings in order, to enhance the bioactivity of titanium implants and to shorten the healing time. Therefore, thin, fully crystalline coatings that are, highly adhesive, hydrophilic and demonstrating antibacterial properties are ly looked for. The aim of this research was to develop and characterize the properties of (nano)hydroxyapatite coatings implemented with nanocopper particles and obtained by the electrophoretic method. The deposition was carried out on the Ti13Zr13Nb alloy, either on a bare surface or a nanotubular oxide layer. The deposition was made for 1 or 2 min. The chemical composition, phase composition, coating structure, homogeneity, thickness, nanoindentation and nanomechanical properties, adhesion determined by a nanoscratch test, and wettability measured by a contact angle were investigated. The presence of nanotubular oxide layers caused no significant change in nanoindentation and nanomechanical propertie and an increase in adhesion strength and a decrease in the contact angle. The increase in deposition time resulted in an increased thickness, a decreased hardness, an increased adhesion strength and wettabilty. The observed effects in the composite (nano)HAp/Cu – (nano)TiO₂ coatings are attributed to the change in the structure of coatings following the increasing deposition time and coating thickness.