Wood powder as reinforcing fillers and polyethylene as a matrix have been used for wood plastic composites (WPC). In preparing WPC, counting agents (such as MA and MAOMS) were also used in order to improve the bonding force between matrix and fillers. In this study, the effect of wood powder, MA, MAOMS concentration on the mechanical properties and interface phenomena on the composites was evaluated The tensile strength of 3wt% MA-treated composites reached its maximum value of 25.91MPa while 3wt% MAOMS-treated composites attained the maximum value of 22.48MPa. The maximum impact strength of MA and MAMOS-treated composites were 44.38J/m and 36.09J/m, respectively, when 3wt% of coupling agent was introduced.

To obtain fine dispersion of Ag particles in (123) superconductors, 123 samples were made by pyrophoric synthetic method using malic acid and the subsequent solid- state reaction. As the pyrophoric synthetic powder was used as a precursor material, fine 123 powder of submicron size was produced in a short reaction time. The added O was converted to metallic Ag during Pyrophoric reaction and it accelerated both the formation of 123 phase and the grain growth via the enhanced mass transfer. The Ag particles of the sample sintered using the pyrephoric synthetic powder were more finely dispersed in the 123 matrix, compared to those of the sample sintered using the mechanically mixed powder, attributing to the improvement of the superconducting properties.

thin films were deposited on Si and Ru/Si substrates by rf magnetron reactive sputtering and annealed in oxygen atmosphere(1atm) to investigate their thermal stability and diffusion barrier property. thin films were thermally stable up to 700\ulcorner for 10min. in oxygen atmosphere and showed excellent barrier property against the interdiffusion of silicon and oxygen. After annealing at , however, volatilization to higher oxide occurred at the surface and inside of thin film and diffusion barrier property was also deteriorated. When annealed at , thin film showed a different microstructure from that of thin film annealed at 75. It is likely that surface defect structure of , , and excess oxygen had an influence on the mode of volatilization with increasing annealing temperature.

To investigate the effect of V and Sb on the corrosion behavior of Zr- based alloys, corrosion tests were performed on 6 kinds of Zr alloys in an autoclave at for 100 days. The transition of the corrosion rate occurred in the sample containing 0.1wt.%V after 10 days but did not occur in the samples containing 0.2wt.%V and 0.4wt.%V. The corrosion resistance of V containing alloys increased with increasing V contents from 0.1 to 0.4wt.% and the alloys containing 0.4wt.%V showed the best corrosion resistance. In the ternary alloys containing 0.1wt.%Sb and 0.4wt.%Sb, the corrosion rate increased significantly from the short exposure time. It was observed that the optimal Sb content for corrosion resistance was 0.2wt.%. The size and volume fraction of precipitates increased with increasing V and Sb contents. The superior corrosion resistance was observed in the Zr alloy having precipitate size of 0.11-0.13. From the result of corrosion behavior and the obserbation of precipitates, the optimal size of the precipitate appear to control the electron conduction in the cathodic reaction and play an important role in maintaining a stable oxide microstructure.

The crystallization behaviors and electrical conductivities of the glasses heat-treated at various times and temperatures in the CuO-BiO-VO glass system were investigated. Among glass samples with various compositions, the highest conductivity obtained in the 31CuO-14BiO-55VO (mol%) glass sample. The 31CuO-14BiO-55VO (mol%) glass sample crystallized by heat treatment at 358 for 8h had 2.6710 /, which was much high value as a solid electrolyte. Compared to the glass sample, the heat- treated glass sample was increased in conductivity by an order of 10-10due to the formation and growth of BiVO and CuVOcrystals.

The sliding wear behavior of Ni-base hardfacing alloy, Deloro 50, was investigated at the contact stresses of 15ksi and 30ksi under the various wear environments. In air at room temperature, Deloro 50 showed lower wear resistance than Stellite 6 even at 15ksi due to the occurrence of severe adhesive wear. This seems to be caused by the lower hardness and work- hardening rate of Deloro 50 than those of Stellite 6. In water at room temperature, Deloro 50 showed as good wear resistance as Stellite 6 at 15ksi. It was considered to be due to that water could effectively prevent metal to metal contact through contacting asperities. However, Deloro 50 showed severe adhesive wear at 30ksi in water at room temperature. It seems to be that the water could not suppress adhesion wear at 30ksi. At in air, Deloro 50 exhibited higher wear resistance than Stellite 6 even at 30ksi. It was considered that the oxide glaze layers formed on wear surface during sliding, effectively prevented direct metal-to-metal contacts

For vacuum seated panel, stresses and displacements in the glass plate were calculated. The geometric variables for our experiment were the thickness of glass plate, the size of panel and the width of sealing line. The fracture behaviors and displacements of its under the vacuum were measured. From the measurement of strains and fracture, it was considered that the maximum stress acted at the middle of the sides of the panel. The stresses and displacement distribution of manufactured panels were greatly dependent on the width of the sealing line in the panel. The measured values are more similar to the values which were calculated from the condition of built-in edge as the width of the sealing line is larger. The measured displacement of the panel, made of 3mm thick glass plate, with size of and 20mm sealing line was . This value is similar to calculated value, , from built- in edge condition in the finite element method.

The possibilities of producing Al-10%Ti-4%Fe composites through in-situ processing and thus achieving mechanical property improvements over binary Al-10%Ti to a level or higher exhibited by PM SiC/A12124 composites were explored in this study. The microstructure of in-situ processed Al-10%Ti-4%Fe composites was similar to that of Al matrix composites reinforced with discontinuous SiC particulates(SiC/A12124) and significant enhancements in elastic modulus, tensile strength and wear resistance were observed as compared to Al-10%Ti alloy. These results can be attributed to the in-situ formed Al. Fe by third element addition, leading to additional dispersion strengthening effect over phase reinforcement in Al-Ti system.

By the mechanical alloying method Ni-W(WC) composite materials were prepared to improve the resistance for creep and sintering of Ni-anode at the operating temperature of. Amorphization was observed from the XRD analysis of mechanically alloyed powder caused by the destruction of ordered crystals. Sintering was performed at for 10 hours in atmosphere. From the result of dot-mapping and TEM analysis the second phase was not observed at Ni-W interface while W particles of less 0.lam were distributed finely and uniformly in Ni matrix. This finely and uniformly distributed W in Ni matrix is expected to enhance the mechanical properties of Ni-anode through the dispersion and solid solution hardening mechanisms.

In this study, ferroelectric PMN powders and thin films were fabricated from metal alkoxide- based solution by sol-gel process. PMN thin films were deposited on platinum coated silicon substrate by dip coating method. The properties of PMN gel powders and thin films such as organic decomposition behavior and crystalline phase transformation de pending on heating temperatures were investigated th rough thermal analysis, FT-IR, Raman spectroscopy, and XRD. Also, the effects of addition of excess PbO and MgO to the perovskite crystal phase formation on PMN thin film were investigated The film thickness formed on platinum coated silicon substrate with S coating cycles was about 3000 after heat treated at for 1min. When the PMN thin film was prepared with 15% excess PbO and heated at for 1min., the single phase perovskite was obtained. We confirmed the fact that in sol- gel process, the formation of the perovskite phase increased with the addition of excess MgO(10m71%), which is consistent with the result observed in the solid phase reaction. Values of dielectric constants and dielectric loss(tan) of PMN thin films deposited on platinum coated silicon substrate and heated at for 1 min. were 2200~2700 and ~0.033 (at 10kHz), respectively

The crystallization behaviour of perovskite for the samples heat- treated at various temperatures for various times in the , glass system has been investigated by the means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. Higher crystallinity obtained in the sample heat-treated at higher temperature for longer time. With increasing heat-treatment time, dielectric constant of the samples heat-treated at and increased, but that of the sample heat- treated at decreased. Loss tangent of the heat-treated samples was not much influenced by heat-treatment conditions. Piezodielectric charge constant was approximately $1.0\times10^{-12}~8.010^{-12}C/N$ in the samples heat-treated at for 1h, 2h, and 8h.

The PZT films were deposited on the Pt/Ti//Si substrates using multi- target DC magnetron reactive sputtering. The perovskite single phase with the composition close to the stoichiometric one, was obtained even at high substrate temperature of by 2-step method, which is that PZT film was deposited for a short time at low substrate temperature () to promote the nucleation of perovskite phase by reducing the volatility of Pb oxide molecules, followed by the deposition at the elevated temperature to suppress the excess incorporation of Pb component in the PZT film. This two-step method, in combination with the RTA treatment, gives rise to good electrical properties of the deposited PZT films: remanent polarifaion,C/; coercive field, 45kV/cm; leakage current of 10 A/ at high electric field of -500kV/cm

Aluminium sulfate solution was prepared by sulfuric acid treatment from gibbsite. Aluminium sulfate hydrate [ · ] was precipitated from aluminium sulfate solution by adding it into ethylalcohol. From XRD analysis as-prepared · was confirmed to have mixed-crystalization water(n=18, 16, 12, 6). The average water of crystalization calculated from thermogravimetry(TG) was 14.7. Aluminium sulfate hydrate [ · ] was thermally decomposed and converted to at , at , and at . Ni-doped , was synthesized from the slurry of as-prepared , with the ratio of [Ni]/[Al]=0.5. The reaction conditions of synthesis were determined as initial pH 9.0 and temperature The basicity(pH) of slurry was controlled by using urea and solution. Urea was also used for deposition-precipitation. For determining termination of reaction, the data acquisition was performed by oxidation reduction potential(ORP), conductivity and pH value in the process of reaction. Termination of the reaction was decided by observing the reaction steps and rapid decrease in conductivity. On the other hand, BET(Brunauer, Emmett and Teller) and thermal diffusity of Ni- doped , with various content of Ni were measured and compared. Thermal stability of Ni- doped at was confirmed from BET and XRD analysis. The surface state of Ni-doped was investigated by X-ray photoelectron spectroscopy(XPS). The binding energy at increased with increasing the formation of phase.

A single crystal cast blade was manufactured by CMSX 6, one of the first generarion nickel based single crystal superalloys by the selector method in a vacuum furnace. The single crystal has been grown with cooling rate of 2.5 mm/min, after pouring the molten alloy of 163 to the mold heated to 150. The cast structure could be classified into matrix (dendrite) and eutectic regions in 'shape and size. The eutectic region showed higher Ti content. As the additional results of 'precipitates by EPMA and CBED analysis the 'size was less than 0.5~0.7, showing the chemical composition close to NiAl of Ll lattice structure. But 'size has increased to bigger than 1.0, being near to eutectic region, changing its shape to bar or huge block types. These showed the chemical structure near to NiTi of D lattice structure. Therefore, 'morphology of dendrite and eutectic regions depends absolutely on its chemical composition and lattice structure.

PZT films without lower electrode were deposited on the highly doped Si(100) substrate with MgO buffer layer (Mgo/si) by RF magnetron sputtering method followed by the rapid thermal annealing at . We investigated the dependences of the crystalline and electrical properties on the MgO thickness and the RTA post annealing. The PZT films on bare Si (without MgO) showed pyrochlore crystal structure while those on MgO(50 )/Si substrates showed the typical perovskite crystal structures. From SEM and AES analysis, the thickness of PZT films was about 7000 showing relatively smooth interface. The depth profiles indicated that atomic species were distributed homogeneously in the PZT/MgO/Si substrate. The dielectric constant( ) and remanent polarization(2Pr) were about 300 and C/;, respectively. The leakage current was about /A.

Characteristics of high frequency induction- hardened bearing steel have been investigated using 0.55wt.% C-1.68wt.% Mn specimens produced by vacuum induction melting (VIM). The K4 value in DIN 57602 of the specimens was assessed to be 6.41, high level of cleanliness. The specimens were high frequency induction-hardened to form heterogeneous submicron- lath martensite in the surface hardened layer with about 2.5mm in effective depth. Rolling contact fatigue tests were conducted in elasto-hydrodynamic lubricating conditions under a maximum Hertzian contact stress of . It was found that microhardness in the subsurface, up to about in depth, below the raceway of rolling contact fatigued specimens was increased in comparison with that of induction-hardened layers. The depth of maximum microhardness- increased region was about from surface, showing white etching area. Crack initiation and propagation in the white etching area below the raceway of rolling contact fatigued specimens were observed.

High quality -bilayers were formed on the Si(100) substrate at room temperature and at first by coevaporation of stoichiometric Si and Ti(Si:Ti = 2:1) fellowed by Ti reactive deposition in N, gas ambient, and in situ annealing in ultrahigh vacuum. Stoichiometric , films with (111) texture and films were grown by annealing at temperatures above . /Si(100) interface was clear and flat without agglomoration, and film was epitxailly grown. The sheet resistance of the - bilayer decreased as the annealing temperature increased and about was obtained from the sample annealed over .