Pressureless sintering to obtain high density boron carbide-titanium diboride composites by in-situ reaction was studied. Pressureless sintering behavior of this material was investigated between 1800-2150 .The effects of composition, sintering temperature and tine were examined. Density up to 98.5% T.D. was reached at 2150. Maximum values of flexural strength (502 MPa), hardness (33 Gpa) and fracture toughnes (4.6 MPa·m1/2) were observed in the specimens containing 15 vol.% TiB2.

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Lead zirconate titanate(PZT) powder with fibroid morphology was prepared via hydrothermal synthesis and heat treatment using organic mineralizer, tetramethylammonium hydroxide pentahydrate (TMAH). The structure and morphology of the resultant fibers were investigated by X-ray diffraction (XRD) analysis and transmission electron microscope (TEM) observation, The TMAH concentration, hydrothermal reaction time, calcining temperature, calcining time both had effects on the microstructure and morphology of the fibrous PZT. The result was analyzed and discussed to confirme the parameters of hydrothermal synthesis technics. Besides, the changes of dielectric constant and dielectric loss with frequencies were investigated in detail. Fibrous PZT powders was pressed into slice, calcined, coated with electrode and polarized. The piezoelectricity capability detection results indicated that piezoelectricity constant increased linearly along with electric voltage.

This discussion reviewed the occurrence of stress corrosion cracking (SCC) of alloys 182 and 82 weld metals in primary water (PWSCC) of pressurized water reactors (PWR) from both operating plants and laboratory experiments. Results from in-service experience showed that more than 340 Alloy 182/82 welds have sustained PWSCC. Most of these cases have been attributed to the presence of high residual stresses produced during the manufacture aside from the inherent tendency for Alloy 182/82 to sustain SCC. The affected welds were not subjected to a stress relief heat treatment with adjacent low alloy steel components. Results from laboratory studies indicated that time-to-cracking of Alloy 82 was a factor of 4 to 10 longer than that for Alloy 182. PWSCC depended strongly on the surface condition, surface residual stresses and surface cold work, which were consistent with the results of in-service failures. Improvements in the resistance of advanced weld metals, Alloys 152 and 52, to PWSCC were discussed.

The oriented La modified PZT thin films were prepared on Pt/Ti/SiO2/Si substrate by the LB technique. The pre-sintering temperatures and the annealing temperatures for La modified PZT were determined by TG-DTA curves and XRD detect results. XRD detection of PZT and PZT with different La amount illustrated the crystal constructions and the effects by modification. The AFM observation of PLZT thin films with organic acid indicated that the LB technique could obtain smooth and flat film with the deposition of PLZT particles within nanometers on substrate. The detection results of the electrical properties indicated that the modification of La had great influence on the electric properties of LB thin film. PLZT thin film by annealing at 650°C had better dielectric constant of 569.2 and dielectric loss of 0.4915 at 5 kHz. And the amount of La of 2% in mass gave the piezoelectric constant of 14pC/N.