等离子喷涂Al2O3+TiO2复合陶瓷涂层的组织结构

利用ＳＥＭ,ＴＥＭ,ＥＤＡＸ及Ｘ射线等手段研究了Ａｌ２Ｏ３＋ＴｉＯ２／ＮｉＣｒＡｌＹ复合陶瓷等离子喷涂层的组织结构,涂层呈片层状,Ａｌ２Ｏ３＋ＴｉＯ２陶瓷涂层由γ－Ａｌ２Ｏ３,ＴｉＯ２及少量的α－Ａｌ２Ｏ３组成,由于喷涂层温度比较高,部分熔化的Ａｌ２Ｏ３和大部分熔化的ＴｉＯ２发生了一定程度的互熔,形成了Ａｌ２Ｏ３＋ＴｉＯ２共晶组织。片层内由Ｎｉ基固溶体及弥散分布其上的γ相（Ｎｉ３Ａｌ）组成,片间为     

W18Cr4V钢表面激光熔覆Al2O3陶瓷涂层的组织结构

研究了Ｗ１８Ｃｒ４Ｖ钢表面Ａｌ２Ｏ３／ＮｉＣｒＡｌ复合陶瓷涂层的组织结构、成分分布及界面组织特征。结果表明：Ａｌ２Ｏ３／ＮｉＣｒＡｌ复合陶瓷等离子喷涂层的组织呈层片状,面层由α－Ａｌ２Ｏ３和少量的γ－Ａｌ２Ｏ３组成,层间为机械结合界面,界面处成分变化梯度较大。经激光重熔后的面层组织为单一的α－Ａｌ２Ｏ３柱状晶,Ａｌ２Ｏ３与中间合金ＮｉＣｒＡｌ间存在明显的界面反应,且界面相增多,在ＮｉＣｒＡｌ与基体     

激光熔覆Al2O3+TiO2复合陶瓷涂层的微观结构

研究了４５＃钢表面Ａｌ２Ｏ３＋ＴｉＯ２复合陶瓷激光熔覆层的微观组织和相结构、Ａｌ２Ｏ３＋ＴｉＯ２复合陶瓷激光熔覆涂层由α－Ａｌ２Ｏ３,ＴｉＯ２,γ－ＴｉＯ２,γ－Ａｌ２Ｏ３及Ａｌ２ＴｉＯ５相组成,消除了等离子喷涂层的层状组织特征,形成了大致方向的柱状晶,晶内为溶入了Ｔｉ及少量底层元素的α－Ａｌ２Ｏ３;晶界为由ＴｉＯ２和Ａｌ２Ｏ３形成的Ａｌ２ＴｉＯ５相,溶有少量的Ｃｒ,Ｆｅ,Ｙ取代了Ａｌ２ＴｉＯ５     

SiCw／涂层／TZP陶瓷复合材料界面化学键的XPS和IR研究

本文用ＸＰＳ和ＩＲ测定了ＳｉＣｗ／（Ａｌ２Ｏ３，莫来石）涂层／ＴＺＰ陶瓷复合材料的界面化学键。结果表明ＳｉＣｗ／Ａｌ２Ｏ３、莫来石、ＴＺＰ界面为化学结合而Ａｌ２Ｏ３、莫来石／ＴＺＰ界面为物理结合。     

Al2O3-CoCrAlY 复合陶瓷激光熔覆层的组织与性能

研究了Ａｌ２Ｏ３－ＣｏＣｒＡｌＹ复合陶瓷涂层的组织结构、成分分布及其耐磨性能。结果表明：等离子喷涂层的组织呈层片状,面层由α－Ａｌ２Ｏ３和少量的γ－Ａｌ２Ｏ３组成,层间为机械结合界面,涂层平均硬度为８９７ＨＶ０．２。经激光重熔后的组织为单一的α－Ａｌ２Ｏ３柱状晶,在ＣｏＣｒＡｌＹ与基体间有界面相形成,其界面为冶金结合,层间存在着平缓的成分过渡;Ａｌ２Ｏ３与ＣｏＣｒＡｌＹ间的界面结合状况得到了明显的     

复合钢管内衬陶瓷层的组织结构和耐腐蚀性能研究

利用铝热－离心法制备了内衬陶瓷复合钢管。通常，陶瓷层由α－Ａｌ２Ｏ３和铁铝尖晶石两相组成。α－Ａｌ２Ｏ３沿径向呈枝晶生长，ＦｅＯ；Ａｌ２Ｏ３连续分布在α－Ａｌ２Ｏ３的枝晶间。由于ＦｅＯ；Ａｌ２Ｏ３不耐酸腐蚀，结果陶瓷层不具有耐酸蚀性能。     

ZrO2添加剂对β“—Al2O3性能的影响

研究了氧化锆添加剂对β”－Ａｌ２Ｏ３陶瓷的显微结构和性能的影响。实验结果表明，添加１０％（按体积计）ＺｒＯ２可以大大改善β”－Ａｌ２Ｏ３陶瓷的显微结构，并使其强度有显著提高，与此同时，β”－Ａｌ２Ｏ３的电导率下降不多。     

β“—Al2O3陶瓷的强化和韧化

研究了稳定ＺｒＯ２和部份稳定ＺｒＯ２对β”－Ａｌ２Ｏ３陶瓷的强化和韧化作用，观察了不同种类、不同含量的ＺｒＯ２对β”－Ａｌ２Ｏ３陶瓷的显微结构、力学性能和电导率的影响，探讨了β”－Ａｌ２Ｏ３的韧化机理。     

硬质合金粉末表面涂层陶瓷的材料

利用溶胶－凝胶法在ＴｉＣ粉末,（Ｗ,Ｔｉ）粉末表面涂层Ａｌ２Ｏ３陶瓷,通过热压烧结制得了两种新型涂层的刀具材料（ＦＴＣ１和ＦＴＣ２）,粉末涂层材料ＦＴＣ１和ＦＴＣ２的力学性能满足刀具材料的使用要求。利用扫描电镜观察发现基体粉末表面较均匀地涂覆了一层α－Ａｌ２Ｏ３陶瓷,并对材料的力学性能和微观结构进行了分析。     

热压Al2O3—ZrO2（6mol%Y2O3）陶瓷复合材料的组织性能研究

本文考察了全稳定ＺｒＯ２对Ａｌ２Ｏ３陶瓷的组织性能的影响。结果表明，热压Ａｌ２Ｏ３－ＺｒＯ２（６ｍｏｌ％Ｙ２Ｏ３）陶瓷材料的显微形貌与其它Ａｌ２Ｏ３－ＺｒＯ２陶瓷的几乎完全一样，小量ｃ－ＺｒＯ２的存在可促进Ａｌ２Ｏ３陶瓷的烧结并细化晶粒，从而提高材料的力学性能，但其增韧增强能力有限。大量ｃ－ＺｒＯ２的存在因其本身低的力学性能、缺乏相变韧化和存在残余拉应力而使材料的力学性能下降。     

B4C--SiC/C复合材料氧化过程的TG/DTA分析

制备了Ｂ_４Ｃ－ＳｉＣ／Ｃ复合材料,对不同组成的复合材料在２０１５００℃升温氧化过程进行了ＴＧ／ＤＴＡ（热重和差热联用）分析。结果表明,复合材料具有不同的高温抗氧化性能,此差异可归因于以下几方面：复合材料的组成不同（包括陶瓷粒子的种类、含量）,不同种类的陶瓷粒子氧化转变成陶瓷氧化物的温度、速率不同,生成的陶瓷氧化物在高温下的物性（对基体材料的润湿性、粘度及流动性、挥发性和对氧的扩散系数等）不同。通过在炭基体中弥散Ｂ４Ｃ粒子可明显提高炭基体在８５０℃以下的抗氧化性。当复合材料中Ｂ４Ｃ含量较高而ＳｉＣ含量低时,样品表面将趋于形成Ｂ２Ｏ３较为富集的硼硅酸玻璃相,在１５００℃以下具有良好的氧化防护效果;当样品中ＳｉＣ含量较高时,在高温下（＞１２００℃）,随着部分Ｂ２Ｏ３的挥发和大量ＳｉＯ２的生成,样品表面将趋于形成ＳｉＯ２较为富集的硼硅酸盐玻璃相,在高达１４００℃以上仍具有良好的氧化防护效果     

离心铝热法制造陶瓷衬里复合管 Ⅲ.中试研究

采用离心铝热法成功地制造了７６～４２６ｍｍ、长２０００ｍｍ的陶瓷衬里复合碳钢管。给出了生产原料、生产装置和生产工艺，讨论了陶瓷层厚度不均匀、陶瓷层疏松、陶瓷层大块剥落、钢管局部穿孔、钢管弯曲的原因，并提出相应的工艺改造措施。     

The tribological and electrochemical behavior of HVOF-sprayed Cr3C2–NiCr ceramic coating on carbon steel

High Velocity Oxygen Fuel (HVOF) is an excellent approach to prepare a good, wear-resistant lamella of Chromium Carbide-Nickel Chrome (Cr₃C₂–NiCr) on carbon steel for high temperature application. This research investigates the effect of a thin, deposited layer of Cr₃C₂-NiCr on carbon steel in terms of wear and corrosion properties. The microstructure of the HVOF-sprayed Cr₃C₂–NiCr coating was characterized at each step by scanning electron microscopy. Wear testing was performed with a pin-on-disk tester. Wear weight loss was examined by applying different loads over a 9048.96 m sliding distance. Experimental results show that the wear resistance of the coated sample reduced the risk of seizure compared to the uncoated sample. An electrochemical test was also performed and the behavior of the substrate in the coated sample was investigated in 3.5% NaCl for 27 days. Electrochemical Impedance Spectroscopy (EIS) showed that the HVOF coating has high corrosion resistance and protects the substrate from NaCl electrolyte penetration. So deposition this layer of ceramic composite is protected oil piping from synergistic attack of seawater during the transport of crude oil to the refinery.     

Microhardness and wear resistance of Al2O3-TiB2-TiC ceramic coatings on carbon steel fabricated by laser cladding

Al₂O₃-TiB₂-TiC ceramic coatings with high microhardness and wear resistance were fabricated on the surfaces of carbon steel substrates by laser cladding using different coating formulations. The microstructures of these ceramic coatings with the different coating formulations were investigated using X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometer. The wear resistance and wear mechanism were analyzed using Vickers microhardness and sliding wear tests. The results showed that when the amount of independent Al₂O₃ was increased to 30%, the ceramic coatings had a favorable surface formation quality and strong metallurgical bond with the steel matrix. The cladding layer was uniformly and densely organized. The black massive Al₂O₃, white granular TiB₂, and TiC distributed on the Fe substrate significantly increased the microhardness and wear resistance. The laser cladding ceramic coating had many hard strengthening phases, and thus resisted the extrusion of rigid particles in frictional contact parts. Therefore, the wear process ended with a “cutting-off” loss mechanism.     

Al2O3—TiB2陶瓷刀具材料的研制及其耐磨性能研究

本文研制成功了一种新型陶瓷刀具材料即Al_2O_3-Ti B_2陶瓷刀具材料。文中讨论了该材料的研制方法,力学性能和微观结构特点,并对该材料的磨损行为和磨损机理进行了研究。结果表明:Ti B_2粒子的弥散可以明显提高该材料的耐磨性。加工淬火钢时该材料的抗磨损能力明显优于Al_2O_3-TiC陶瓷刀具材料。Al_2O_3-Ti B_2陶瓷刀具材料的磨损过程主要受粘着、耕犁和微破损机制的控制。     

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。     

交变磁场对重力SHS制备复合管微观结构和机械性能的影响(英文)

将交变磁场引入自蔓延高温合成反应,研究其对Al2O3复合管陶瓷层结构和力学性能的影响.结果表明:交变磁场可以促进燃烧反应的进行,随着磁感应强度的增加,α-Al2O3的枝晶尺寸减小,形态逐渐向细小的等轴晶形态过渡.复合管的抗压强度和抗剪强度随着磁感应强度的增加而增加.其中当磁感应强度为0.20T时,抗压强度和抗剪强度分别达418MPa和19.5MPa,比未引入交变磁场前分别提高了19.1%和21.9%.     

离心铝热法制造陶瓷衬里复合管 Ⅱ.陶瓷不锈钢衬里复合管的探索

探索了离心铝热法制造陶瓷不锈钢衬里复合管的工艺,研究了复合管中陶瓷层、不锈钢层和碳钢层的金相组织特征,讨论了衬里层出现缺陷的原因,并提出相应的工艺改进措施。     

普碳钢用陶瓷基高温防护涂层制备及其性能表征

采用机械混合法制备了一种针对碳钢的新型Al2O3-MgO-TiO2-CaO体系陶瓷基高温防护涂料,1300℃下可在Q235B钢表面形成致密保护层,提高钢抗氧化烧损性能.结果表明,在涂料粒度48～75μm、涂层厚度0.5mm的条件下,涂层防护性能优良.涂层的防护温度范围为900～1300℃,1300℃时比原样可降低氧化烧损59.36%,防护寿命长于8h.涂层的应用将氧化层由经典的Fe2O3/Fe3O4/FeO三层结构转变为一层尖晶石结构,同时减薄了氧化层厚度,显著降低了Fe元素的高温扩散速率.     

Behaviour of the wettability of a SiAlON-base ceramic by molten steel

The purpose of this work is to investigate the wettability and the corrosion of a SiAlON ceramic with amorphous carbon additive (5, 10 and 20 wt.%) by a SiCa treated liquid steel. The carbon additive provokes a change in the substrate nature during the sintering process. Meanwhile these substrates are not wetted and exhibit a relatively good resistance to the corrosion by molten steel mainly because of the formation of a continuous alumina layer on the substrate resulting from SiAlON oxidation. An analysis of the solid–liquid interface allows explaining the corrosion mechanisms.