The present research shows that the composite with Ti (or its alloys) as a substrate and commercial porcelain as its coating has been proved to be
quite effective to resolve bio-compatibility problem since the porcelain, which contains mainly Al₂O₃, SiO₂, K₂O, Na₂O, possesses best bio-
compatibility with human tissues. Moreover, the above composite adding a thin layer of Si₃N₄ between the Ti substrate and porcelain coating has
been proved to be even more effective to resolve present problem due to the adhesion between the substrate and the porcelain coating quite strengthened.
These composites are successfully applied to the present application and may open new application fields since the problems have been effectively resolved. The present investigation not only gives the chemical composition, the
technical process and the performance of the composites, but also gives their microstructure details.

The relationship between the orientations of tetrahedral [WO₄]^2- in tungstate crystals with the scheelite and wolframite structures such as CaWO₄,
PbWO₄, NaBi(WO₄)₂, CdWO₄, ZnWO₄ and FeWO₄, which are all the important scintillation materials, and their morphology was studied from the standpoint
of crystal chemistry, and the formation mechanisms of their morphology were analysed according to the structural orientations of tetrahedral [WO₄]^2-
and the bonding energies between [WO₄]^2- and metal ions [M²⁺ ] during growth. It is shown that the morphology of tungstates is related to the orientations
of structural units [WO₄]^2- and [M---O₆] or [M---O₈] in these crystals and similar to that of sulfates. The structural features of ABO₄ compounds
were compared, and the relationships between structures and growth habits discussed.

Using lead acetate, lanthanum nitrate, calcium acetate and butyl titanate as reactants, weprepared nano-sized (Pb_0.88Ca_0.04La_0.08)Ti_0.98O₃ (PCLT) powders (10~60 um) by sol-gel process.The nano-size powders were obtained by means of sintering with the different annealing temperatures and time. The synthesis was investigated by DTA, TGA and XRD. The size and morphologywere tested by TEM. The nanocrystalline PCLT sample was also characterized by FTIR.

Nanocrystalline Sr--Cr hydrogarnet was synthesized from a relatively mild hydrothermal system. High solubility of the initial of species and highly concentrated mineralizer
lowered the crystallization temperature and enhanced the crystalinity. With increasing temperature, OH bondings to the Sr dodecahecra were broken, and in air or O₂, oxidation
from Cr(Ⅲ) to Cr(Ⅵ) occurred. Valence variation of the framwork Cr ions determined the decomposition process and the structural types of the decomposition products.
Nanocrystalline Sr--Cr hydrogarnet is paramagnetic, and the complete quenching of the orbitle monument was observed. Highly symmetric Cr--OH octahedra were revealed.

The resistance to hydrolysis of aluminium nitride (AlN) powder was improved by coating oleic acid (OA) and 8-hydroxyquinodline (HQ) on the surface of AlN particles.
The treated powders did not react with water at 40℃ when soaked for up to 70h at a constant pH, whereas at the same conditions the untreated AlN reacted with water
after 2～10h soaking. However, with an increase of temperature (60～80℃),the hydrolysis of the coated powder took place quickly. The hydrolysis kinetics of AlN
powder with OA and HQ films was divided into two steps, diffusion control stage and chemical reaction control stage, both of which were first order reactions with activation
energies about 125kJ/mol and 114kJ/mol respectively. The observed behavior was interpreted by the hydrophobic films as a diffusion barried between water and AlN surface, which
was responsible for the improvement of the hydrolysis resistance. The hydrolysis of the coated AlN powders at high temperature was attributed to an interfacial physical
bonding that was easily broken down by errosion of water. This explanation was supported by TG--DTA, XRD and IR examination.

β-Ni(OH)₂ nano-particles were produced by homogeneous precipitation method and anhydrous ethanol method. The Characteristics of the nano particles were studied by XRD, TG, DTA,TEM and ICP. It was found that the effect of main factors including the kind of surface activeagent, the transform condition of crystal type and the aftertreatment temperature, on the sampleperformance was great. The performance of the charge/discharge cycles was also studied.

The micromechanisms and characteristics of fatigue crack-growth in Sialon ceramics withdifferent microstructures were studied. Under cyclic loading, stress corrosion, wear degradation ofasperities through friction and indentation damage were used to explain the fatigue crack-growthbehavior. The samples of higher content of rod-like β-Sialon grains with larger aspect ratio,showed higher resistance to fatigue crack growth, thus higher reliability under cyclic loads at roomtemperature.

Procedures were developed to predict the probability distribution of notch strength of ceramics from the flexural strength of ceramics based on our recent research^[1].
It is shown that the notch strength of ceramics follows the normal distribution, the log-normal distribution and Weibull distribution, and all of the above distributions
can be predicted. The predicted results of three probability distributions of notch strength of ceramics mentioned above are in good agreement with test results. The possibility
of predicting the probability distribution of notch strength of ceramics is of practical importance in the design and the reliability assessment of ceramic structure elements.

Experimental investigation on whisker toughening in SiC_w/ZrO₂(6mol%Y₂O₃) ceramics shows that two main toughening mechanisms, including crack bridging and crack deflection operate simultaneously
during crack propagation. A numerical model of whisker toughening was proposed to estimate the combing toughening contribution from crack
bridging and crack deflection. The calculated results reveal that the load/displacement curve exhibits a zig-zag shape as a result of the repeated crack extension, followed by crack arrest behavior.
With increasing whisker content, both of contributions of crack bridging and crack deflection increase, additionally, the dominant toughening mechanism is gradually changed from crack deflection to crack
bridging. The rationality of the mode was proved with some experimental results.

The influences of particle size distribution and additive contents on properties of ceramicmembrane were investigated. The average pore size, pore size distribution, the porosity, gas andliquid flux were determined. The microporous membranes with average pore size of 0.45μm andporosity of 50% were prepared by solid state sintering technology.

The surface and backside morpologies of diamond thin film as well as the surface morphology of the cobalt cemented tungsten carbide (YG8) insert after
deposited using D. C. plasma jet CVD method were observed by SEM. The cross-sectional morphology and microstructure of a CVD diamond thin film grown onto the cemented carbide insert were studied by means of TEM. Fourier transformated
laser Raman spectrometry was also used to characterize the structure compositions of the diamond thin film deposited and the cemented carbide insert
surface after diamond thin film delaminated. The results show that there exists a thin layer of graphite carbon (tens of nanometers) at the interface of a diamond thin film
coated cemented carbide insert. It has been seen, However, that diamond particles can be grown directly onto WC crystals at partial zones. Typical cross-sectional
morphology of a diamond thin film coated cemented carbide insert formed on the basis of pertreatment processes such as chemically cobalt-removed and plasmaetching
decarbonized treatments is as follows: diamond thin film; graphite carbon thin layer; small WC grains layer, retained decarbonized layer (W and η phases); YG8
cemented carbide substrate.

Ba(Mg_1/3Ya_2/3)O₃ solid-state formation reactions and its sinterability were studied in relation with different raw materials, Ta₂O₅·xH₂O and T₂O₅ raw materials with different
phase structure and grain size were employed as the source Ta₂O₅, along with BCO₃ and MgO. The experiment results indicated that the adoption of
Ta₂O₅·xH₂O can retard the intermediate phase and leads to more complete reaction at lower temperature than that with Ta₂O₅, which is
due to the local stoichiometric homogeneities of the mixed powder and the phase transformation Ta₂O₅ from Ta₂O₅·xH₂O. The sinterability
of the powder prepared from Ta₂O₅·xH₂O is much better than that of the powder from Ta₂O₅.

The O-3 type composites of TGS, BaTiO₃, PZT and LiNbO₃ based on PVDF were prepared.The long term polarization relaxation in these composites was studied. It indicates that there arethree mechanisms with different relaxation time. These mechanisms result from crystalline grainsof the crystal or ceramics, matrix and grain boundaries. A stable polarization results from thegrain boundaries.

Ni-rich Ni/SiO₂ composite aerogels in which weight percentage of Ni could reach 60% werefirstly prepared by sol-gel process of Ni-containing tetraethyl orthosilicate (NiTEOS). The influenceof H₂O, catalyst, solvent and compostcomposition of Ni-containing tetraethyl orthosilicate on the sol-gelprocess was discussed. The specific sufrace areas of Ni/SiO₂ composite aerogels are in the rangeof 420~650m²/g.

The primary phase of K₂O-MgO-SiO₂-CaF₂ glass-Ceramics is tetrasilicic-mica (K₂CaMg₅Si₈O₂₂F₂) , the newly formed crystals in this glass-ceramics are KMg_2.5Si₈ O₁₀F₂ , CaO·MgO·2SiO₂ andK₂CaMg₅Si₈O₂₂F₂ respectively in sequence. The chemical compositions of the final crystals, whichare composed of diopside and richterite, of this type glass-ceramics are almost the same as thoseof the parent glass.

The grain growth and kinetics of nanocrystalline titania prepared by using a precursor methodfrom titanium terachloride were studied. The grain size grew slowly when annealing temperaturebelow 773K but fast above 773K. The grain growth activation energy is 54.62±3.73kJ/mol at T >773K and 6.43±3.39kJ/mol at T <773K.

The gelcasting process for shaping nano-sized Y-TZP was studied. The effect of organicmonomer and binder on the rheological properties of slurry was investigated. There existed the optimum amount of monomer, binder and initiator. Compared to dry pressing and isostatic pressingmethods, the specimens formed by gelcasting had higher density, more homogenous microstructureand higher fracture toughness.

Ultrafine Ti(C,N) powder was synthesized by inorganic sol-gel and carbothermal- reductionprocessing using TiO(OH)₂ and carbon black as starting materials. The thermodynamics of theprocess was analyzed. The effects of the ratio of raw materials, synthesizing temperature, holdingtime and the flow of N₂ on the composition of Ti(C,N) were investigated. Ti(C_1-x.,N_x) powderwith x values of 0.2-0.7 and an average particle size less than 100um can be obtained under properconditions.

The Sb-doped nanocrystalline α-Fe₂O₃ powders were prepared by sol-gel method with FeCl₃·6H₂O as the source
substance. The phase transformation and microstructure of the systems were investigated by XRD, Mossbauer spectrometer, DTA
and TEM. The dry gel is found to be Fe(OH)₃ amorphous phase, it transforms to nanocrystalline α-Fe₂O₃ by annealing at a
certain temperature. When the system is doped with Sb, the impurities distribute on the surface of the Fe(OH)₃ amorphous particles. They have no obvious influence on the inner structure of Fe(OH)₃
but evidently enhance crystallization temperature, thus take the role of restraining the formation and growth of α-Fe₂O₃
grains, and are favourable for obtaining α-Fe₂O₃ nanocrystalline powder.

ZnO nanopowders prepared by the Sol-Gel method were sintered by microwave. The microstructure of the material was analysed by XRD and SEM. The I-V properties
of varistor were measured by a stabilized dc power source. Compared with the conventional sintering, microwave sintering promptes grain growth and shortenes sintering time.
When grain sizes are the same, the temperature of microwave sintering can be lower than that of conventional sinering. Microwave sintering has the ability to enhance the density of
ZnO varistor ceramic and to obtain good electric propertises. Hence, microwave sintering is a newly effective method for processing ZnO varistor ceramic.

Polyphase Y-α/β-Sialon powders were prepared by SHS method, with St, Al, Y₂O₃ and Si3N4as raw materials under high nitrogen pressure. The effects of nitrogen pressure and the amount ofdiluent on α , β phase compositions and the amount of free Si were studied in detail.

The investigations were mainly focused on the phase composition, microstructure and fatigue life of α/β-Sialon
ceramics prepared from powder mixtures of Si₃N₄, AlN, Al₂O₃ and Y₂O₃ by gas pressure sintering. The results obtained show
that the Sialon ceramics material is mainly composed of 70% β-Sialon, 30% α-Sialon with a small amount crystalline
phase and glassy phase on grain boundaries. The cyclic fatigue life testings were conducted by using a commercial servohydraulic machine
operated under load control, with a sinusoidal wave form at a frequency of 25 Hz and load ratios (R) of 0.1. The operations lead
to result that fatigue limit stress is about 75% static strength for this material.

The liquid phase bonding of silicon nitride ceramics by using glass adhesives was studied. The effects of adhesive composition
and joining conditions such as temperature (1450～1650℃) and holding time (10～120min) on the bond strength of the joint were
investigated. The results showed that increasing viscosity of the adhesive by the addition of α-Si₃N₄ powder to the glass, and
consequently reducing fluidity of the adhesive degraded the bond strength. The op