用不同粘土矿物合成Sialon粉末的研究

本文以高岭土、蒙脱石、叶腊石为原料，将粘土矿物与碳混合，加入适量的添加剂，在Ｎ２气氛１４００°Ｃ下，经４ｈ碳热还原氮化合成Ｓｉａｌｏｎ，产物经ＸＲＤ、ＸＰＳ、ＥＰＭＡ等分析，结果表明：用不同粘土矿物合成Ｓｉａｌｏｎ，矿物的Ａｌ／Ｓｉ比与碳的含量直接影响最终的合成产物，但主晶相仍为Ｚ＝３的β′－Ｓｉａｌｏｎ。     

无压烧结合成O＇－Sialon

探讨了Ｏ＇－Ｓｉａｌｏｎ的合成工艺及配方选择；研究了Ａｌ２Ｏ３在Ｓｉ２Ｎ２Ｏ中的固溶状况及添加剂Ｙ２Ｏ３和烧结液相的特点对Ｏ＇－Ｓｔａｌｏｎ中Ａｌ２Ｏ３固溶度的影响．结果表明；无压烧结合成Ｏ＇－Ｓｉａｌｏｎ的工艺应选用ＳｉＣ粉料作为埋粉，通Ｎ２保护；Ｘ＝０．３为Ｏ＇－Ｓｉａｌｏｎ固溶极限的配方；Ｙ２Ｏ３的加入量增多有利于Ｋ１ｃ值的提高；Ｋ１ｃ在Ｘ＝０．３～０．４时达到最大值；配料时应避开靠近低共熔点处（Ｘ＝０．２）的配方，因其试样力学性能较差．     

添加剂对AIN陶瓷力学性能及抗氧化性能的影响

本文研究了Ａｌ２Ｏ３、Ｙ２Ｏ３、Ｌａ２Ｏ３、Ｙ２Ｏ３＋ＳｉＯ２几种类型的添加剂对ＡＩＮ陶瓷力学性能和高温抗氧化性能的影响。结果表明：Ｙ２Ｏ３＋ＳｉＯ２为一种较好的ＡＩＮ陶瓷添加剂，材料在烧结过程中由于２Ｈ＾５Ｓｉａｌｏｎ及８Ｈ－Ｓｉａｌｏｎ等纤维状的Ｓｉａｌｏｎ相形成，对材料起到一种自补强作用，ＳｉＯ２的存在使用ＡＩＮ陶瓷在氧化工程中形成Ｍｕｌｌｉｔｅ保护层，故使ＡＩＮ陶瓷肯有良好的力学性能及高温     

AlN／SiCw（Y2O3＋SiO2）复合材料热处理增强研究

研究了热处理对ＡｌＮ／ＳｉＣｗ（Ｙ２Ｏ３＋ＳｉＯ２）复合材料机械性能的影响。结果表明，该材料经热处理后的强度提高，当添加剂Ｙ２Ｏ３／ＳｉＯ２＝１／２．５摩尔比时，提高幅度最大。经ＸＲＤ，ＳＥＭ，ＴＥＭ／ＥＤＡＸ和ＨＲＥＭ分析，热处理增强的机理主要是粒界玻璃相在高温氧化气氛中和ＡｌＮ颗粒表层作用，生成的纤维２Ｈ＾δＳｉａｌｏｎ相和ＳｉＣｗ形成空间交错结构。     

C3S在NaOH和水中早期水化的ESCA研究

用ＥＳＣＡ研究了Ｃ３Ｓ在水中和ＮａＯＨ溶液中水化１－１０ｍｉｎ试样的表面组成;用等离子发射光谱仪测定了Ｃ３Ｓ早期水化液相中的组成,结果表明：Ｃ３Ｓ早期水化表面组成ｎ（Ｃａ）／ｎ（Ｓｉ）〉３,或ｎ（Ｃａ＋Ｎａ）／ｎ（Ｓｉ）〉３,形成一富Ｃａ层,初步认为Ｃ３Ｓ在ＮａＯＨ溶液中水化,Ｃａ＾３＋溶出受阻而Ｓｉ＾４＋溶出加快：Ｎａ在水化早期进入双电层和表面组成中,实验表明,欲采用ＥＳＣＡ技术测定Ｃ３Ｓ早期水     

微酸性光亮锡铅合金镀液分析方法

提出锡铅合金液中Ｓｎ＾２＋，Ｓｎ（ＩＶ），ＰＢ＾２＋、ＥＤＴＱＡ、柠檬酸三钠的分析方法。     

聚电解质对磷酸钙垢抑制能力研究

采用比较研究的方法，探讨了ＡＡ·ＨＰＡ，ＡＡ·ＡＥＳ、ＭＡ·ＡＡ及ＰＡＡ四种聚电解质在不同浓度，ＰＨ值、Ｃａ＾２＋浓度、ＰＯ４＾３－浓度、温度及恒温时间对聚电聚质阻垢率的影响。研究结果表明，ＡＡ·ＨＰＡ和ＡＡ·ＡＥＳ共聚物具有良好的的阻磷酸钙垢性能、增加聚电解质中羟基含量将降低阻磷酸钙垢的效果。     

高效液膜分离富集镍基合金镀层中稀土总量

用ＴＢＰ－ＴＴＡ（协同流动载体）、ＳＰＡＮ８０和煤油高效液膜体系，研究∑ＲＥ＾３＋迁移行为。在适宜条件下，１０ｍｉｎ内，∑ＲＥ＾３＋的迁移率达９９．５％以上。在同样条件下，常见共存金属离子如Ｆｅ＾３＋、Ａｌ＾３＋、Ｎｉ＾２＋、Ｃｒ＾３＋、Ｍｏ＾６＋、Ｃｕ＾２＋、Ｃｏ＾２＋、Ｚｎ＾２＋、Ｃｄ＾２＋等均不被迁移；大量碱金属、碱土金属、Ｃｌ、ＮＯ３、ＣｌＯ４、Ｆ、ＳｉＯ３＾２－、ＳＯ４＾２－等离子也不影     

羧甲基淀粉吸附剂对水溶液中铬和铝离子的吸附研究

羧甲基淀粉（ＣＭＳ）吸附剂是惭烯接枝到交联淀粉骨架上研制而成的。先用静态法和动态法研究羧甲基淀粉吸附剂对Ｃｒ＾３＋、Ａｌ＾３＋的吸附效果以及ＰＨ值对吸附的影响,然后用不同浓度的ＨＣＩ溶液（０．３～１．２ｍｏｌ／Ｌ）进行解吸,研究吸后Ｃｒ＾３＋、Ａｌ＾３＋的回收情况,并探讨了吸附剂的吸附机理,结果表明：ＣＭＳ吸附剂的静态等温吸附符合２Ｆｒｅｕｎｄｉｌｉｅｃｈ吸等温式,动态吸附的吸附时间大大缩短,明显     

铝硅酸溶胶—MgSiF6—H3PO4系统的^27Al,^29Si,^31PNMR和XRD研究

用＾２７Ａｌ、＾２９Ｓｉ和＾３１Ｐ核磁共振和ＸＲＤ了铝硅酸胶－ＭｇＳｉＦ６－Ｈ３ＰＯ４系统的物相组成及Ａｌ、Ｓｉ、Ｐ在其中所处的结构状态。结果表明，在铝硅酸溶胶中加入ＭｇＳｉＦｔ会导致Ａｌ＾＋５离子从溶胶胶粒中溶出，溶胶胶粒结构的破坏，从而引起胶胶粒中Ａｌ／Ｓｉ比和Ａｌ、Ｓｉ所处结构状态的变化。ＭｇＳｉＦ６与从溶胶胶粒溶出的Ａｌ＾３＋、Ｎａ＾＋离子作用形成水溶性很低的ＮａＭｇＡｌＦ６从而使得铝硅酸     

Preparation and Performance Study of Sialon‐Si3N4‐SiC Composite Ceramics for Concentrated Solar Power

For lowering the sintering temperature of silicon carbide ceramics used for solar thermal energy storage technology, O'‐Sialon and silicon nitride were employed as composite phases to construct Sialon‐Si₃N₄‐SiC composite ceramics. The composite ceramics were synthesized using SiC, Si₃N₄, quartz, and different alumina sources as starting materials with noncontact graphite‐buried sintering method. Influences of alumina sources on the physical properties and thermal shock resistance of the composites were studied. The results revealed that the employment of O'‐Sialon and silicon nitride could decrease the sintering temperature greatly to 1540°C. The optimum formula G2 prepared from mullite as alumina source achieved the best performances: 66.7 MPa of bending strength, 10.0 W/(m·K) of thermal conductivity. The composition parameter x = 0.4 of O'‐Sialon decreased to 0.04 after 30 cycles thermal shock, and the bending strength increased with a rate of 11.0% due to the increase of O'‐Sialon grain size, and the optimization of microstructure caused by the transformation of O'‐Sialon grains and densification within the samples. The good thermal shock resistance makes the composites suitable for the use as thermal storage materials of concentrated solar power generation.     

β-Sialon结合刚玉耐火材料的合成

本研究对βＳｉａｌｏｎ结合刚玉的合成反应进行了热力学分析。并通过改进合成工艺,制备出了氮含量为８．０％,气孔率１３．４％,体积密度３．０４ｇ·ｃｍ－３,耐压强度１６４．８ＭＰａ的试样。试样的ＸＲＤ分析表明,其主晶相为刚玉和βＳｉａｌｏｎ,杂质相含量很少。ＳＥＭ分析显示,试样的结构致密,刚玉颗粒与基质中的βＳｉａｌｏｎ之间的结合牢固     

Synthesis and microstructure evolution of β-Sialon fibers/barium aluminosilicate (BAS) glass-ceramic matrix composite with enhanced mechanical properties

Dense Sialon fibers/barium aluminosilicate (BAS) matrix self-reinforced composite was synthesized by one-step method without applying pressure before or during sintering process. In this work, BAS matrix and internal Sialon fibers were synthesized successfully by directly sintering precursor powders at 1400°C for 4 h. The BAS is not only introduced as a structural matrix material, but also as an effective liquid phase sintering aid to attain full densification bulk sample. The results show that the diameter of fibers is about 100–200 nm, and the quantity of the fibers can be changed with different temperatures. The obtained Sialon fibers/BAS matrix composites exhibit better toughness due to fiber bridging, crack deflection, and pullout. The sample with 3.5 wt% carbon content has maximum value of flexural strength (74.5 ± 3.5 MPa) and fracture toughness (3.2 ± 0.20 MPa·m^1/2). The growth of the Sialon fibers follows a vapor-liquid-solid (V-L-S) mechanism. These findings featured with a green and simple preparation process provide a facile strategy to design and fabricate the bulk ceramic matrix composites in complex shapes and different sizes.     

In situ synthesis of PcBN composites from Sialon–TiN–TiB2 binder and cBN under high temperature and pressure

Polycrystalline cubic boron nitride (PcBN) composites were synthesized in situ with TiB₂, TiN, and Sialon as binders under ultrahigh temperature (1550°C) and high pressure (5.5 GPa). X-ray diffractometry, universal testing machine, field emission scanning electron microscopy, and transmission electron microscopy were used to study the effect of Sialon content (0%, 20%, 40%, 60%, and 80% by mass of binder) on the phase composition, microstructure, and mechanical properties of PcBN composites. The results show that the main phases in the system are lamellar TiN, needle-rodlike TiB₂, and irregular long-rodlike Sialon. Some TiB₂ grows along the (1 0 −1 0) face, and Sialon grows along the (0 0 0 1) face. The density and mechanical properties of the sintered product are significantly improved due to the formation of Sialon. When the content of Sialon is 60%, the binder is uniformly distributed, the cBN interface is well bonded, and the density is the highest. At this time, the strength reaches the maximum 34.57 GPa, the fracture toughness is 6.82 MPa m^1/2, and the flexural strength reaches the maximum 870.79 MPa. On the whole, cBN composites have excellent prospects for future applications in cutting inserts due to their excellent mechanical properties.     

Sialon结合SiC耐火材料的化学稳定性

采用高岭土、炭黑为主要结合相原料,合成了Sialon结合SiC耐火材料。考察了Sialon结合SiC耐火材料的氧化行为、高温碱侵蚀行为和冰晶石熔体的侵蚀行为。结果显示,合成Sialon结合SiC耐火材料具有高的机械强度和化学稳定性。     

赛隆结合耐火材料显微结构分析与生产途径探讨

分析了几种赛隆结合碳化硅砖、刚玉砖的显微结构,从显微结构及赛隆相的形成上探讨了适宜的赛隆结合耐火材料工业化生产的途径。     

Effect of hBN addition on the fabrication,mechanical and tribological properties of Sialon materials

This work aims to investigate the effect of hBN on the friction and wear resistance of Sialon composite. Sialon and its composite with 10 wt% hBN were fabricated by SPS sintering. The effect of hBN additive on the phase composition, microstructure, densification behavior, mechanical and dry sliding tribological properties of Sialon material was studied. Being sintered at 1600 °C for 10 min, compared to monolithic Sialon, Sialon-hBN composite has more refined β-Sialon grains with smaller aspect ratios and slightly declined relative density. The hardness of the Sialon-hBN composite was reduced due to the weak bonding between Sialon and hBN grains. Nevertheless, its fracture toughness increased ascribing to the toughening mechanisms, including crack deflection and crack bridging. hBN had an essential impact on the tribological performances of the composite due to its lower friction coefficient and good lubrication action. Under the same densification level (i.e., with a relative density of around 97.5%), the friction and wear resistance of Sialon-hBN composite were much better than monolithic Sialon. The main wear mechanisms were tribolayer formation, oxidized wear, and abrasive wear.     

Si-Al-O-N系中的新型耐火材料

介绍了Si Al O N系中的新型耐火材料 :Alon结合Al2 O3,Sialon结合Al2 O3,A3S2 -Sialon结合Al2 O3,O’ Sialon结合Al2 O3 及O’ Sialon -ZrO2耐火材料的特点、性能和制备工艺过程 ,为从事新型耐火材料开发的研究者提供有益的参考     

ZrO_2和原位自生TiN复相O′-Sialon的合成机理与表征

通过对TiO2 和ZrO2 在Si3N4 SiO2 Al2 O3体系中的反应过程分析和试验 ,讨论了原位自生TiN/O′ Sialon与ZrO2 /O′ Sialon复相材料的合成机理 ,并利用各种手段分别对所合成的两种材料进行了表征     

Sialon／SiC复相材料研究进展

根据相图，合成Ｓｉａｌｏｎ相的技术途径包括采用Ｓｉ３Ｎ４粉末和其它反应添加物以无压或热压工艺高温合成，或以Ｓｉ粉与其它金属及其氧化物为原料无压反应烧成而成，ｉａｌｏｎ粉末也可通过粘土类矿物的碳热还原反应来合成，但前两种技术作乱在原料及合成工艺上的高成本使其难于在耐火材料领域大规模开发应用，后一种工艺目前仅见到合成Ｓｉａｌｏｎ粉末的试验报道，本研究在对粘土类矿物合成Ｓｉｌａｏｎ粉末的研究基础上，由廉