ZrO2-Ti系材料的热力学分析与显微结构研究

通过热力学数据的预报与计算,对ＺｒＯ_２－Ｔｉ体系的相间热力学稳定性进行了分析,并确定了材料合成的热力学条件．在此基础上常压烧结合成了不同组分配比的ＺｒＯ_２－Ｔｉ系复合材料,并采用ＸＲＤ、ＳＥＭ、ＴＥＭ等方法对材料的显微结构进行了表征．ＺｒＯ_２－Ｔｉ系均质复合材料由α－Ｔｉ相,四方ＺｒＯ_２相和少量的单斜ＺｒＯ_２相组成．ＸＲＤ和ＴＥＭ分析表明,组元Ｔｉ和ＺｒＯ_２之间没有发生明显的化学反应,具有良好的化学相容性．     

ZrO2-Ti系材料的热力学分析与显微结构研究

通过热力学数据的预报与计算,对ＺｒＯ２－Ｔｉ体系的相间热力学稳定性进行了分析,并确定了材料民折和学条件。在此基础上常压烧结合不同组分配比的ＺｒＯ２－Ｔｉ系复合材料,并采用ＸＲＤ,ＳＥＭ,ＴＥＭ等方法对材料的显微结构进行了表征,ＺｒＯ２－Ｔｉ系均质复合材料由α－Ｔｉ相,四方ＺｒＯ２相和少量的单斜ＺｒＯ２相组成,ＸＲＤ和ＴＥＭ分析表明,组元Ｔｉ、ＺｒＯ２之间没有发生明显的化学反应,上有良好的化学相窝性     

Ag-MgF2复合金属陶瓷薄膜的结构与光学特性研究

以真空烧结的Ag-MgF2粉体为蒸发材料,用真空蒸镀法制备了Ag-MgF2金属陶瓷薄膜,X射线衍射、红外以及紫外-可见光谱研究表明:薄膜为由纳米fcc-Ag晶粒镶嵌于主要为非晶态的MgF2基体中构成.在400～1600cm-1波数范围,Ag-MgF2金属陶瓷薄膜具有400～600cm-1的MgF2晶体特征吸收带和Ag-MgF2复合结构产生的730～1250cm-1的吸收谱带;在200～800nm波长范围,Ag-MgF2金属陶瓷薄膜对波长为220～800nm的光波均具有很低的反射率和很强的吸收,对波长为340～580nm的光波吸收率高达85%以上;而在紫外光区,Ag-MgF2薄膜则具有高反射率(＞51%).     

A New Process for Preparing Fine-ceramic-containing Composite Coatings--Flame Spray Synthesis

Flame spray synthesis (FSS), a combination of the flame spray technology and Self-propagation High-temperature Synthesis (SHS) was developed for preparing fine-ceramic-containing composite coatings. It can simplify the preparations of powder to synthesize and deposit the desired materials in one step. The preliminary results obtained from TiC-Fe cermet coatings by FSS process are reported. The peculiar microstructure of the composite coatings, which contains very fine (<1m) and round TiC and alternate TiC-rich (Hv=11?13GPa) and TiC-poor layers (Hv=3.0 -6.0GPa), is expected to play an important role in their tribological properties.     

Preparation and properties of 4.25Cu-0.75Ni/NiFe_2O_4 cermet

1INTRODUCTION NiFe2O4cermets,whichareexpectedtobe usedastheinertanodesforaluminumelectrolysis, havelowcorrosionandoxidation,goodelectricalconductivityandhighthermalshockresistance[15]. Nickelferritespinelformsacorrosion resistant networkthatcontainstheelectricallyconductivecopper basedmetallicphase.Especially,Gregget al[6]foundacermetofNiFe2O4 18%NiO 17%Cu (massfraction),whichshowedfavorablecorrosion andconductivitypropertiesasinertanodesinsmalllaboratorycells.However,itwasalsoshowedth…     

Ag含量对NiFe2O4基金属陶瓷惰性阳极性能的影响

为了提高NiFe2O4陶瓷阳极材料的力学性能和抗热震性,向原料中加入金属Ag,采用粉末冶金法制备了Ag/NiFe2O4金属陶瓷惰性阳极.研究了Ag含量对材料微观结构、抗弯强度以及抗热震性的影响.研究结果表明随着Ag含量的增加,惰性阳极材料的晶粒尺寸逐渐减小,说明Ag能够有效抑制陶瓷基体晶粒的长大.而且随着Ag含量的增加,材料的结构越来越致密,说明Ag在一定程度上能够促进烧结.对材料的力学性能和抗热震性测试结果发现,Ag能提高材料的强度,随着Ag含量的增加,材料的抗弯强度逐渐增大,抗热震性在银含量为10%处达到最大值.     

Ti(C,N)基金属陶瓷功能梯度材料的制备

利用热等静压技术高温高压的特点,在金属陶瓷的基体上获得了硬质梯度涂层.借助扫描电镜、X射线衍射仪、显微硬度计和电子探针分析技术对N化后材料的组织、结构、性能进行了测试分析.结果表明,高温高压N化能在表面形成硬质梯度薄膜,表面区域N的活度梯度是促使各合金元素迁移形成氮化表面层特征组织的最终驱动力.表面硬度和心部韧性提高,并且硬度由表及里逐渐减小,这是由于高温高压氮化处理使材料中的孔洞闭合,微裂纹和缺陷的减少使得材料的性能得到显著提高.     

Spark Plasma Sintering Preperties of Ultrafine Ti （ C, N）-based Cermet

Ultrafine Ti( C, N)-based cermet was sintered by SPS from 1050℃ to 1450℃ and its sintering properties, such as porosity, mechanical properties and phase transformation , were investigated by optical microscopy ( OM ), scanning electron microscopy (SEM), X-ray diffraction ( XRD ), and differential scanning calorimeter (OSC). It is found that the spark plasma sintering properties of Ti ( C, N )-based cermet differ from those of conventional vacuum sintering. The liquid phase appearance is at least lower by 150℃ than that in vacuum sintering. The porosity decreases sharply belove 1200℃ and reaches minimum at 1200℃ , and afterwards it almost keeps invariable and no longer increases. SPS remarkably accelerates the phase transformation of Ti ( C, N )-based cermet and it has a powerful ability to remorse oxides in Ti( C, N)-based cermets. Above 1350℃, denitrification occurred. Fresh graphite phase formed above 1 430℃ . Both the porosity and graphite are responsible for the poor TRS.     

三元硼化物金属陶瓷覆层材料耐腐蚀性能研究

以Mo粉、FeB合金粉和Fe粉为基本原料，分别加入Cr、Ni、C或同时加入Cr、Ni、C合金元素成分，采用原位反应真空液相烧结工艺，在Q235钢基体上制备三元硼化物金属陶瓷覆层材料。研究了合金组分对覆层材料耐腐蚀性的影响。结果表明，三元硼化物金属陶瓷覆层材料的覆层具有远比钢基体优越的耐蚀性，C组分的单独加入降低了覆层的耐蚀性，Cr、Ni组分的加入显著提高了覆层的耐蚀性，同时加入Cr、Ni、C作为合金组分使覆层具有最佳的耐蚀性。     

铝电解陶瓷类惰性阳极材料的发展

对了铝电解对惰性阳极材料的要求进行了说明。介绍了多种对金属氧化物陶瓷材料和金属陶瓷材料为基体惰性阳极的实验室研究及工业试验情况，并阐述了对添加剂对阳极性能的影响。