Cubic boron nitride (c-BN) attracts widespread interest as a promising material for many potential applications because of its unique physical and chemical properties. Since the 1980’s the research in c-BN thin films has been carried out, which reached its summit in the mid of 1990’s, then turned into a downward period. In the past few years, however, important progress was achieved in synthesis and properties of cubic boron nitride films, such as obtaining >1μm thick c-BN films, epitaxial growth of single crystalline c-BN films, and advances in mechanics properties and microstructures of the interlayer of c-BN films. The present article reviews the current status of the synthesis and properties of c-BN thin films.

Nanocrystalline Ni_1-x Zn_xFe₂O₄ ferrite with 0≤x≤1, was successfully prepared by a spraying-coprecipitation method. The microstructure was investigated by using TG-DSC, XRD, SEM, TEM as well as BET. Magnetic properties were measured with a vibrating sample magnetometer (VSM) at room temperature. The results show that uniform and fine nanocrystalline Ni_1-xZn_xFe₂O₄ ferrite powders are obtained by the spraying-coprecipitation method. The grain size is about 30 nm calcined at 600 for 1.5h. There are a few agglomerates with average sizes below 100nm. The specific saturation magnetization of nanocrystallineNi_1-x Zn_xFe₂O₄ ferrite increases with the concent of Zn²⁺ at room temperature, and maximum σs is 66.8A·m²/kg as the content of Zn²⁺ is around 0.5. When the grain size is 41nm, the coercivity Hc of nanocrystalline Ni0.5Zn0.5Fe2O4 ferrite arrives at 5.06kA/m, and then it decreases with the increase of the grain size. The results may be explained in terms of intense random magnetocrystalline anisotropy model in nanocrystalline materials.

The formation of tin dioxide nanotubes on tin substrates anodizing in oxalic acid electrolytes and annealing in the air was investigated. Under optimized electrolyte, oxidation and anneal conditions, nanotubes of tin dioxide were fabricated. Topologies of the anodized tin change remarkably along with applied voltages, electrolyte concentration and oxidation time. Field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD) and poresizer indicate the nanotubes are formed due to the competition of tin monoxide formation and dissolution under the assistance of electric field. The formation mechanism of nanotubes agrees with the theoretic model of oxidation-dissolution.

Cubic tantalum nitride (TaN) nanocrystallites were synthesized by the direct-current (dc) arc discharge method in N₂ gas. The influence of N₂ pressure on the as-synthesized cubic TaN samples was studied. The growth mechanism of cubic TaN was discussed. XRD, TEM and XPS were used to characterize the product. The results show that the influence of N₂ pressure plays a key role in the preparation of pure cubic TaN nanocrystallites. The size of cubic TaN nanocrystallites obtained is 5--10nm.

By using the hydrothermal method, the ZnO nanorod arrays with different morphologies were synthesized on ZnO nanoparticle-coated transparent conductivity glasses (TCO) at low temperatures by controlling the pH value of precursory solutions. The ZnO nanorod arrays were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), high-resolution transmission electron microscope (HRTEM) and ultraviolet-visible spectrophotometer (UV-Vis). Furthermore, the mechanism was primary discussed. The results show that the ZnO nanorod is a single crystal and it grows along c axis. When the pH value is about 10.5, the array is well-aligned and the diameter of the nanorod is uniform. Optical characterization shows that the optical transmittance of the film is higher than 80% in the visible wavelength and its band gap is about 3.25eV.

Functional ultrafine fibers of polycarbonate (PC)/TiO₂ were prepared by electrospinning of PC solutions mixed with butyl titanate for possible anti-bacterial applications. Three different mixture ratios, i.e. 9:1, 8:2, and 7:3 by mass between PC and butyl titanate were applied. These fibers were then characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Furthermore, anti-bacterial performance of the nonwoven fiber mats on escherichia coli was also measured. Experimental results show that when the ratio of PC and butyl titanate is 9:1, the resulting fibers are most uniform with least beads on the fiber surfaces. When this ratio is increased to 7:3, however, as high as 87% of the escherichia coli bacteria are killed. The present work demonstrates that an attachment of titania into PC ultrafine fibers leads to a significant improvement in their anti-bacterial ability.

CdSe nanorods with different structure phases were prepared by a hydrothermal method, and the products were characterized with TEM, SEM, XRD, TGA-DTA. The results show that the CdSe nanorod with zinc blende structure is formed at 200℃ reaction temperature. At 240℃ reaction temperature, the wurtzite structure CdSe nanorod can be obtained.The IPCE of the wurtzite structure CdSe nanorod film electrode is higher than that of zinc blende structure CdSe nanorod film electrode. The wavelength with the max IPCE value for the CdSe/PMeT composite film electrode appears as red shift.

Carbolic ink mixed with a few tiny silicon powders was adopted to fully immerse polyacrylonitrile (PAN) based carbon felt then dried it, and as the result of such reactions as carbon thermal reduction etc, with gaseous outcomes generated from tiny silicon powders at 1450℃ in vacuum, abundant SiC nano-threads were fabricated within the inner space of the carbon felt. There exist many SiC nano-threads with tortuous pattern, their diameters are within the range of 25nm to 150nm, and detectable lengths of them can be more than 15μm. There also exist various SiC structures such as membranes, nano-blowballs, nano-particles, and so on. Characterizations for the sintered sample of XRD, SEM, and TEM analyses were carried out, and components, microstructures of the sample as well as growth mechanisms of the nano-threads were preliminarily studied.

Mullite continuous fibers were prepared in Al₂O₃-SiO₂ system by separately adding FeO, Na₂O and MgO with a melt/drawing method. The forming mechanism of mullite was investigated by using SEM, XRD and SEM-EDS. The results show that the mullite fibers with a needle structure can be prepared from the method. This is a new approach of preparing mullite continuous fibers in industry which comes from producing glass fibers process with a crucible.

The modulation of polyacrylamide (PAM) on the morphology and phase compositions of calcium oxalate crystals was investigated by means of scanning electron microscopy and X-ray powder diffraction. The effects of the concentration of polyacrylamide, pH value in solution and the supersaturation of calcium oxalate on the crystallization of calcium oxalate were discussed. PAM can induce the formation of calcium oxalate dihydrate(COD) crystals and change the morphology of COD and calcium oxalate monohydrate (COM) crystals. In the presence of 5.0g/L of PAM, about 30 percentage (w/w) COD crystals were induced, the aggregated COD crystals were observed, and the shapes of COM crystals were changed from elongated, twinned and aggregated to oval. These results were discussed from the points of molecular structure of PAM, the hydrolysis difference of PAM at various pH values, the interaction between the carboxylic groups of PAM and Ca²⁺
in solution, the complexation-dissociation balance between the PAM and Ca²⁺ ions on the surface of COM crystals, and electrostatic interaction etc. The results obtained show that by changing the experimental conditions calcium oxalate crystals with various phase and morphologies can be prepared.

Superfine powders of La _2/3-x Li _3x TiO ₃(x=0.11, LLT) perovskite-type oxides were synthesized by a citrate method. The factors influencing on the formation of sol and gel as well as the crystal structure and morphology
of synthesized powders were examined. The effects of sintering temperature on the conductivities of the ceramics were investigated. The results show that the highest electrical conductivity can be obtained for the sample sintered at 1200℃, which is approximately 150℃ lower than that of samples synthesized by the conventional solid state reaction method. The grain and total lithium ion conductivities of the LLT ceramics sintered at 1200℃ are 9×10^-4 S/cm and 2.15×10^-5 S/cm at room temperature, respectively.

The solid electrolyte interface and its formed-behavior on silicon anode, which mainly occur during the first lithium ion insertion, were detected and analyzed by EIS, EDS and XPS. The results show that the SEI film on silicon electrode surface forms under a low lithium-inserting voltage. The thickness of SEI film increases with the
depth of the state of discharge. The depth XPS analysis of the electrode surface demonstrates the inhomogeneous characteristic of SEI film. LiF and Li₂CO₃ are the major lithiated components including in SEI film, whereas Li₂CO₃ more approaches to the surface exposed to the electrolyte and LiF is more close to the side of silicon electrode. Some trace of
silicon-containing compound, which might be the reacting product of electrolyte and silicon electrode, exists in SEI film.

Electrochemical impedance spectroscopy (EIS) was applied to study the reaction kinetics of layer lithium cobalt nickel manganese oxide material. Effects of the battery structure, charge depth and temperature on the layer lithium cobalt nickel manganese oxide cathode electrodes were tested by EIS. The results show that the inductance appears in the 18650 winding cells while not in 2032 cells. The whole process consists of overcoming strcture force period of oxygen layers crystal lattice in the rang of 2.0--2.7V, lithium-ion membranes forming period in the range of 2.7--3.65V and interface electrical double layer forming period in the range of 3.65--4.25V.The charge transfer rate and Li-ion diffuse rate are improved with temperature increasing. The charge transfer and lithium ion diffusion activation energies are 20.48kJ/mol and 48.67kJ/mol respectively, so the lithium ion diffusion process is the control process of the whole electrochemical reaction.

A novel technique was employed to preparing LiV₃O₈ in which LiOH·H₂O and NH₄VO₃ were used as the raw materials. The structure, morphology and properties of the sample were investigated by XRD, TGA/DTA, TEM, charge-discharge and CV. The results of XRD and TEM show that different calcining temperatures result in different structure and morphology, which lead to different discharge capacities. The specific discharge capacity of the sample calcined at 300℃ for 6h, in the range of 1.8--3.8V, is up to 342mAh/g in the first cycle. The capacity of the sampl is decreased with the increase of calcining temperatures.

The effect of Y₂O₃ and ZnO on the microstructure and dielectric properties of BaTiO₃ materials was researched. XRD indicates the crystal structures of BaTiO₃ transform from tetragonal to pseudocubic by Y₂O₃ and ZnO codoping. SEM shows Y₂O₃ behaves more effective grain-growth-inhibition than ZnO owing to the intergranular second-phase Y₂Ti₂O₇. Sufficient Y₂O₃ and ZnO can help to form the core-shell structure and improve the dielectric-temperature characteristics markedly. The high performance nonreducible dielectrics satisfying X7R can be achieved in the BaTiO₃-Y₂O₃-ZnO new system.

In order to improve the microwave absorption of the absorber, the compound particles of barium titanate coated with carbon black were synthesized by a sol-gel method. The microstructure and morphology of the compound powders were characterized, and dielectric properties and microwave absorption property of the composite
were investigated. XRD and TEM results show that carbon black nano-films are well coated on the surfaces of barium titanate particles. The barium titanate particles are spherical, loosely agglomerate with sizes in the range of 50--70nm, and the coated film is 10--20nm thick. The dielectric and microwave absorption properties of the compound particle are improved. The results indicate that compound particles have different effects on the microwave absorption performance of the composites with different compound particle contents. When the weight content of compound particles filling to epoxide resin matrix exceeds 20wt%, the microwave absorption performance of the composite with the compound particles and epoxide resin can be improved greatly.

By means of ferroelectric differential hysteresis loop spectra, the polarization fatigue of Ba _0.99 Sr _0.01 TiO₃ ceramics was carefully studied. The effects of conductance, paraelectrics and pure ferroelectrics could be definitely separated. The results show that the polarization fatigue arose from 180° domain appears much faster than that arose from 90° domain. Ferroelectric differential loop spectra are proved to be a much more powerful method to describe polarization fatigue than traditional hysteresis loop.

Lead-free piezoelectric(Na _0.52 K _0.48-x Li _x)(Nb _0.86 Ta _0.10 Sb _0.04)O₃ ceramics were prepared by solid state reaction. The microstructure, phase and electric properties were studied for (Na _0.52 K _0.48-x Li _x )(Nb _0.86 Ta _0.10 Sb _0.04 )O₃ samples with different Li content (x being 0, 0.02, 0.04, 0.06, 0.08). Results show that their phases, piezoelectric, dielectric and ferroelectric properties of (Na _0.52 K _0.48-x Li _x)(Nb _0.86 Ta _0.10 -Sb _0.04) O₃ lead-free ceramics are μch influenced by the content of Li ions. The piezoelectric properties are enhanced when Li content increases from 0 to 0.04, and decreased when Li content (x) is more than 0.04. Best electric properties are obtained for the sample when x equals 0.04,with its piezoelectric constant d33 being 260pC/N, dielectric loss tanδ being 0.027, planar coupling factor k p being 50%, remanent polarization P r being 22μC·cm^-2, coercive electric field E c being 0.95kV·mm^-1, Curie temperature being 316℃. With the increase of Li content, the coercive electric field E c increases obviously, and the Curie temperature is also enhanced.

Dense lead free ceramics of (K _0.5 Na _0.5 ) _0.96 Sr _0.02 Nb _1-x Mn _x O ₃ (x=0,0.01,0.02,0.03,0.04) were successfully prepared by a conventional mixed oxide method. The X-ray diffraction patterns revealed pure peroveskite structure after Mn doping as compared to the original composition. This was attributed to the inhibition of K⁺ volatility during sintering process. Dielectric anomaly was observed and explained by multiple-cell structure resulting from Mn-induced lattice distortion. Low loss tangent and relatively high planar electromechanical coupling factor were obtained at x=0.02. The main parameters for the composition of x=0.02 are: ε^T₃₃/ε₀=479, d₃₃=121pC/N K_p=41%, Q_m=298, tanδ=1.6%, T_c=391℃. The rates of resonant frequency variation, α_fr, and planar coupling factor variation, α_Kp, with temperature are --1.85% and 1.19% at 80℃, respectively. This material may be suitable for applications in ultrasonic transducers.

MnZn ferrites and NiZn ferrites were prepared by conventional ceramic processing techniques. The frequency dependence of permeability of MnZn ferrites with Fe-poor composition (less than 50mol% of Fe₂O₃) was studied. Tri-segment frequency dispersion model which consists of domain wall motion, magnetization rotation and gyro-magnetic spin rotation was used to simulate the permeability spectra of ferrites. Effects of Fe₂O₃ and TiO₂ content on
permeability of Fe-poor MnZn ferrites were also studied to analyze contribution of the simulating parameters.

The composite piezoelectric ceramics with periodical ferroelectric domains were prepared by traditional composite technology, and the bulk ceramics with periodical ferroelectric domains were produced by a periodically poling method. The thicknessshear resonance and frequency properties of those two kinds of periodical ferroelectric domain ceramics were investigated. It is concluded that periodical ferroelectric domain structure can effectively restrain the bad effect from longitudinal or radical high order harmonious oscillation, and thickness shear resonance frequency can be increased by the periodically poling method, therefore the piezoelectric ceramics with inductance characteristics could be produced by the method of resonance and antiresonance at some frequency region through adjusting the size of periodical ferroelectric domain.

Perovskite La _1-x Sr_xCoO₃ ( x=0.2,0.4,0.6,0.8) catalysts based on porous mullite fiber ceramic were prepared by a vacuum impregnation method. The samples were characterized by XRD, SEM and BET, respectively. The La(OH)₃ crystal phase was detected besides the perovskite structures in La_1-x Sr_xCoO₃ catalysts, and the La(OH)₃ peaks become sharp as x decreases. Tridimensional netshape of support and the good dispersing particles of catalysts based on support were detected by SEM. Specific surface area of La _1-xSr_xCoO₃ increases with the degree of substitution x of Sr for La via BET tests. Catalytic activity of La _1-x Sr _x CoO₃ catalysts prepared for CO+NO was tested. The results indicate that La _1-x Sr _x CoO ₃ catalysts have a best catalytic activity, when partial substitution of Sr for La reaches the optimal substitution fraction ( x=0.2).

Concentrated SiC slurry with Y₂O₃ and Al₂O₃ as sintering assistants was prepared, by using the medium of gelcasting premix solution and pH adjusting reagent of TMAH (tetramethylammonium hydroxide). The measurements of Zeta potential, sedimentation and viscosity show that SiC, Y₂O₃ and Al₂O₃ can disperse well in premix solution at basic region. Rheological study clarifies that concentrated SiC gelcasting slurry has low viscosity and shear stress after adding 0.5wt% TMAH, which is suitable to cast into the mold. The green body formed by gelcasting was pressureless sintered at 2000℃ for 1h. SEM image of SiC ceramic indicates that the structure of SiC sintered body is homogeneous and no obvious defects existing. The relative density, flexural strength, hardness and toughness of SiC sintered body are (98.1± 0.2)%, (722±70)MPa, (20.18±0.75)GPa and (4.00±0.20)MPa ．m ^1/2, respectively.

Wear resistance of alumina, alumina/silicon carbide composite and alumina/mullite composite was determined by abrasive wear tests. Microstructure of the samples was observed by transmission electron microscope (TEM). Morphologies of the worn and fracture surfaces were analyzed by scanning electron microscope (SEM). The influence of fracture mode and wear surface pullout on wear resistance was studied. The results are listed as follows, the main wear mechanisms of alumina and alumina/silicon carbide are fracture wear and plastic wear respectively, and as alumina/mullite composite is concerned, fracture wear and plastic wear mechanism exerted combined effect. Compared with that of alumina, wear resistance of alumina/silicon carbide compsosite and alumina/mullite composite is improved by 2--4 times. The primary source for the improvement is the reduction of area fraction of pullout induced by fracture mode transition.

The rare-earth luminescent materials coated with Si and Al were prepared by the sol-gel route. The result of FL measurement indicates that the coated sample has the similar luminescent properties to that of the uncoated. The compositions, microstructure, texture and surface morphology of the binary films containing Si and Al elements were investigated by SEM,XRD,BET and XPS. Water-resistance of the coated and uncoated samples was evaluated by measuring the pH of water in which the samples were dispersed. The results show that a thin dense binary film containing Si and Al elements forms on the surface of the sample through chemical interactions, which can enhance the uncoated sample’s stability under water-containing conditions.

Molybdenum carbide, prepared by temperature-programmed reaction(TPR), using CH₄/H₂ gas mixture to carburize molybdenum trioxide, was characterized by TG-DTA, XRD, BET, SEM and XPS techniques. The results indicate that molybdenum carbide can be prepared by the pathway of MoO₃→MoO₂→MoO_xC_y→Mo₂C in CH₄/H₂ mixture to carburize molybdenum trioxide by TPR, and the proper carburizing temperature is about 675℃. The phase of molybdenum carbide is β--Mo ₂C, the particles with the dimension of about 3.9μm are orderly and uniform. It is found that the XPS spectra of Mo3d included two peaks, one is due to Mo--C identified to Mo ²⁺ which is the dominant species and the other is due to Mo--O identified to Mo ^δ+ . The four peaks of C1s spectra are corresponding to C--Mo, C--C, C--H and C--O species respectively, and the C-- Mo is the dominant species. The particle size of Mo2C is aggrandized, the BET area decreased, and free carbon of the surface increased with the increase of carburizing temperature, furthermore the Mo atoms on the surface are mainly in the form of Mo--C identified to Mo ²⁺ , and only a small part is passivated by oxygen, because of the cover and
protection of free carbon.

The expanded graphite composites with iron oxides adsorbed were prepared by expanding the mixture of ferrocene and expandable graphite under high temperatures. The main components of iron oxides were Fe₂O₃, Fe₃O₄. With the increase of iron oxides contents, the mean conductivity of the composites dropped slowly, however, the magnetization intensity strengthened gradually. Without prejudice to the electric loss absorption of expanded graphite, the magnetic loss absorption of composites was increased. Compared with pure expanded graphite, the 3mm, 8mm wave dynamic attenuation performances of the composite were obviously superior. The 3mm, 8mm wave dynamic attenuation capabilities were strongest, when the weight ratio of ferrocene and expandable graphite was (2--3):5.

A novel cathodic co-electrodeposition (CCED) method for the preparation of Fe ³⁺ -doped TiO ₂ thin film (Fe-TiO ₂) was studied. The thin film photocatalysts of Fe-TiO ₂ containing different amounts of Fe ³⁺ were prepared by the
CCED, wet impregnation and sol-gel methods. The photocatalysts were characterized by X-ray diffraction analysis (XRD), specific surface area measurements, SEM-EDS and UV-vis absorption spectra. In the three types of photocatalysts, the photocatalysts obtained by CCED not only have a more homogeneous distribution of Fe ³⁺ , but also have the largerst specific surface area and the photodegradation activity than those obtained by the other two. In addition, the experimental results show that there is a synergetic effect of photosensitization and photocatalytic in RhB degradation.

Undoped and Mn-Mg co-doped barium strontiun titanate (Ba_0.25Sr_0.75TiO₃) thin films were deposited on Pt/Ti/SiO₂/Si substrates by a sol-gel technique. X-ray diffraction (XRD) analysis and FE- SEM reveal that the films exhibite a pure perovskite phasestructure, uniform grain sizes and crack-fee. The dielectric constant, loss, tunability and leakage current density are 200, 0.010, 38%, 1×10 ^-5 A/cm ², respectively, at a 1mol% Mn-Mg content. The improved BST thin films can be used for tunable microwave devices.

Polypyrrole/Titanium Oxide (PPy/TiO ₂) nanocomposite thin films prepared by in situ chemical oxidation polymerization and electrostatic self-assembly combined technique were investigated. The films were characterized with UV-Vis spectroscope and atomic force microscope. With the assistance of interdigitated electrodes, gas sensors using PPy/TiO ₂ nanocomposite thin films were achieved. The sensitivities of sensors to toxic gases NH3 and CO at room temperature were studied. Temperature and humidity sensitive properties were also tested. The results show that the sensor can detect NH ₃ with high sensitivity, whereas can not recognize CO almost. The investigation of the effects of film depositing time on sensor sensitivities shows that the sensors with the composite thin film deposited for 20min possess the highest sensitivity to NH₃.

Improving the infrared transmission of sapphire can increase the reliability and accuracy of infrared detector. SiO₂ coatings were prepared on sapphires by radio frequency magnetron reactive sputtering. Infrared transmissions of coated and uncoated sapphires at high temperatures and after rain erosion tests were investigated. Results show that the prepared SiO₂ films can increase the transmission of sapphire in mid-wave IR greatly. At high temperatures, SiO₂ films have an anti-reflective effect on sapphire substrates and so the coated sapphires have a higher average transmittance than the uncoated ones. After rain erosion tests, average transmission decreases a little in the wavelength range from 3 to 5μm for coated sapphires. In addition, sapphires coated with SiO₂ films have a higher transmittance than uncoated ones after rain erosion.

The external aluminium layer was transformed into a ceramic coating by the treatment of plasma electrolytic oxidation (PEO) on aluminized steel. Characteristics of anodic voltage, thickness growth regularity, cross-sectional morphologies and compositions of the ceramic coating were investigated. The results show that the anodic voltages of aluminized steel and pure aluminum vary similarly at the initial PEO stage, but the voltage of aluminized steel decreases at later PEO stage. The aluminium layer is consumed, and the ceramic-coating thickness increases linearly. The FeAl layer begins to participate in PEO process as the aluminium layer is transformed completely into the ceramic coating. Nevertheless, the ceramic coating grows slowly and many micro-cracks are observed at the Al₂O₃/FeAl interface. The ceramic coating is mainly composed of Al, Si and O elements. It consists of γ-Al₂O₃, mullite, and α-Al₂O₃ phase appearing only at the last PEO stage. The hardness distribution of the coating is regional and the maximum is about HV 1800.

A microstructure investigation of TiN/Si₃N₄ nanocomposite films with high hardness was performed by means of high-resolution transmission electron microscope, and a result far from the nc-TiN/a-Si3N4 model was presented. Instead of the isotropic one, TiN was pronounced nanocrystalline columnar grains with dimensions of <10nm in width and >100nm in length. Immiscible Si₃N₄ interfacial phases between TiN nanocolumns with a thickness of about 0.5--0.7nm existed in nanocrystalline structure and formed coherent interfaces with adjacent TiN nanocrystals. A succedent simulation employing two-dimensional TiN/Si₃N₄ nanomultilayers also implied that due to the template effect of crystalline TiN layers, sputter-deposited amorphous Si₃N₄ was forced to crystallize and grow epitaxially with TiN layers when its thickness was less than 0.7nm, accompanied by a significant enhancement in film’s hardness. Due to the short-range nature of the template effect of TiN layers, the
crystalline Si3N4 gradually transformed into amorphous when its thickness exceeded 1.0nm and the coherent interfaces were destroyed as a consequence, with a simultaneous film’s hardness decline. By comparing the microstructure and corresponding hardness response of TiN/Si₃N₄ nanocomposite films with that of the nanomultilayered ones, a new explanation on hardening mechanism of TiN/Si₃N₄ nanocomposites was proposed.

The even single phase β-FeSi₂ thin films were prepared by femtosecond laser deposition on Si (100) and Si (111) wafers using a FeSi₂ alloy target. X-ray diffraction, field scanning electron microscope (FSEM), energy dispersive X-ray microanalysis (EDX), Fourier-transform Raman infrared spectroscope (FTRIS) were used to characterize the structure, composition, and properties of β-FeSi₂ films. The growth of β-FeSi₂ depends on the orientation of Si substrates. The photoluminescence from the grown single phase β-FeSi₂ thin film observed at room temperature (2℃) is at a wavelength of 1.53 μm. Raman peaks of β-FeSi₂ observed by an Raman microscope with 514.5nm argon laser are at 192.9cm^-1, 243.9cm^-1 and other positions.

By static combustion synthesis tests, Ti-B₄C-C+5wt%Al was chosen as the reactive system to prepare the Ti(C_0.7, N_0.3)-TiB₂- Al₂O₃ multiphased ceramic coatings on the metal substrate with a reactive flame spray technology. It is found that the coatings have the multiphased heterogeneous metastable structure, which consists of TiC_0.7N_0.3, TiB₂, Al₂O₃, titanium oxide and some pores. The structure of the coatings can be divided into three kinds: the Tistructure with the cluster-shaped TiB₂ in micron-nanometer size, the structure with mass-shaped 1--2μm Ti(C_0.7, N_0.3) particle surrounded by the needle-shaped or strip-shaped TiB₂ and the black phase of anomalous pores. The forming causes of the three kinds of structure are the same as those of the coatings with no additive Al. However the additive Al raises the reaction velocity, so the amount of ceramic phase increases, the structure becomes fine, the pores reduce and the micro-hardness of the coatings is increased.

In K₂ZrF6 solution, the ceramic coatings composed of a large amount of t-ZrO₂, m-ZrO₂ and a little γ-Al₂O₃ and KZr₂(PO₄)₃ were prepared on LY12 aluminum by a micro-arc oxidation technique. With the increase of micro-arc oxidatin (MAO) time, the content of crystalline substances is increased, the coating surface roughness is increased, and the compactness of the coating is improved. The thickness of the coating is increased approximately linearly, and the hardness and the corrosion resistance are both improved, while the heat shock resistance of the coatings turned worse. Meantime, the friction tests
show that the anti-abrasion of the coated samples is improved to a large extent, the friction coefficient of the substrate is about 2/3 that of the coated samples. With the increase of MAO time, friction weight loss of the coated samples is first increased, and then decreased, while the friction coefficient is decreased.

According to the test results of the bonding strength and microhardness of nanostructured AT13 coatings prepared by micro-plasma spraying on conditions of different processing parameters, using genetic algorithms and neural networks, the non-linear model on the relationship between the properties of nanostructured AT13 coatings and the process parameters was set up and simulated. The optimization was based on the genetic algorithms and multi-objective optimization theory. The results show that the simulated results agree with experimental values, and the relative error is less than 0.5%. The optimum parameters are that spraying current is 150A, argon flow is 0.64m³/h, argon pressure is 0.38MPa, and the overall properties of nanostructured AT13 coatings are the best.

The temperature sensibility of amorphous diamond (a-D) films deposited with the filtered cathodic vacuum arc technology was investigated in the range of -190-600℃. The samples cooled by liquid nitrogen pump were $in~situ$ measured on a Linkam stage and the samples for thermal stability were heated in a furnace. The microstructure and mechanical properties were respectively examined by visible Raman spectroscopy and a nanoindenter. The results show that a-D films have better thermal stability in air, they can hold their hardness up to 400℃ and hold their structure up to 500℃. However, the complete material loss takes place at about 600℃. Raman measurements show an apparent shift of the G-peak frequency to higher values with increasing annealing temperatures. The films are not sensitive to lower temperatures. The microstucture of the films remains stable as temperatures are decreased to -190℃.

The Macro-texture, grain boundary distribution and surface morphlolgy in CVD free standing diamond films deposited with different methane concentrations were observed by X ray diffraction technology, electron backscatter diffraction and SEM. The crystal growing process of {100} and {111} planes in diamond crystal was studied. It is shown that diamond films adsorb activated radical CH₂^2- on {100} plane or adsorb CH₃^- and CH₃^- on {111} plane alternately. Carbon atoms stack on the film surface during dehydrogenation. At low methane concentration, the expansion ratio of {111} planes is close to, but faster
than that of {100} planes because of their relative lower surface energy. The enhanced driving force induced by the increased methane concentration results in faster growth of {100} plane than that of {111} plane, which promotes the formation of {100} texture. The film surface morphology consisits of the exposured {100} planes that are parallel to the film surface and the exposured {111} planes area as the side surface that decrease during the competition growth, which is different from that of single crystal growth.