The cathode was synthesized with TiO2, CaO and C as raw materials,and then TiC powders were prepared by electrolysis in CaCl2-NaCl mixed molten salt. The resultant cathode and its electrolytic product were characterized by SEM, EDX and XRD. The results show that under 1 300℃ sintering temperature and 2 h sintering duration,CaTiO3-C compound with favorable electrical conductivity and strength can be obtained to meet the requirement of molten salt electrolysis for cathode. With the resultant compound as cathode,TiC powders with irregular spheroidal distribution and uniform particle sizes can be obtained by molten salt electrolysis.

The causes are analyzed for high solid content of crude TICl4 produced by molten salt chlorination. It is pointed out the high solid content of crude TICl4 is caused mainly by raw materials,chlorination temperature and molten salt composition in the molten salt chlorination section, the temperature of dust collection chamber and chamber connection pattern in the dust collection section, scrubbing temperature and circulating pump tank allocation in the scrubbing section as well as the stirring rate and settlement time in the settlement section. The related countermeasures are discussed.

Sr and Ba separation is a technical difficult problem in the production of high compounds. The principle,characteristics and application of main methods for Sr and Ba viewed,and the study orientation for Sr and Ba separation is also discussed.

Precursor solution was prepared through ultrasonic vibrating and setting,and then ulltra-fine RE-doped MoO3 powder was prepared by hydrothermal synthesis through the modification of the solution pH value, synthesis temperature and filling rate. Finally, nanometer-sized RE-doped Mo powder was produced after two-stage hydrogen reduction. MoO3 powder was characterized by XRD and SEM. The results show that nanometer-sized RE-doped Mo powder synthesized under the conditions of pH=0.5,180℃ synthesis temperature and 90% filling rate has fine and uniform particle size and good dispersibility.

The Ti-Nb-Cr-C doped molybdenum alloy was prepared by powder metallurgy, and its microstructure, particle size and composition were analyzed. Thermodynamics was discussed of oxide generation during ball milling and carbide formation during sintering. The results show that the second phase particles are mainly distributed on the grain boundary, and also distributed inside the grain when Nb content is eno- ugh. The second phase mainly contains Nb,Ti and C,possibly being composite carbides of Nb and Ti based on the thermodynamics analysis. The second phase particles can refine the grains of molybdenum alloy, and the effect of grain refinement is strongest with Nb content of 3 %. Cr exists in molybdenum alloy mainly in the form of solid solution.

Yttrium aluminum garnet （YAG） ceramic fibers were prepared by sol-gel with aluminum chloride,aluminum powder,yttrium oxide and acetic acid as raw materials. Boric acid was added into YAG precursor sol to study the effects of boric acid on the spinnability of sol,and crystallization temperature and microstructure of YAG fibers. The results indicate that addition of boric acid has no effect on the sol spinnability. Upon 2 h calcination at 1 000 ℃ ,YAG gel fibers are fully crystallized into YAG. The addition of boric acid can improve the fiber crystallization and decrease the crystallization temperature. Larger grains and intergranular voids can be observed on the surface of the fibers with boric acid.

The thicker 93W-4.9Ni-2.1Fe tungsten heavy alloy sheets were prepared by powder rolling-stacking sintering. The comparison of microstructure and properties was conducted between single sintered tungsten alloy sheets and stacking sintered ones （i. e. thicker tungsten alloy sheets）,and the influences of cold-rolling on microstructure and properties of stacking sintered alloy sheets were studied. The results show that the thicker tungsten heavy alloy sheets can be prepared with homogeneous microstructure and well combined layers by powder rolling-stacking sintering, and their relative density, hardness and tensile strength are comparable with those of single sintered alloy sheets. Moreover,the mechanical properties of stacking sintered alloy sheets are improved significantly by cold-rolling. Therefore, powder rolling-stacking sintering is effective for preparation of the thicker tungsten heavy alloy sheets.

Abstraet..W-10Cu composite materials were prepared by high velocity compaction-cold forging-copper infil tration. Meanwhile,investigation was made on the influences of particle size and single sample weight of W powders on the microstructure and properties of the materials. The results show that the relative density of W skeleton decreases with the increase of single sample weight before and after cold forging. Upon compaction of the mixed powders,W skeleton has the greatest relative density,yet it is not satisfactory to W-10Cu composite material,of which the relative density should be no less than 81%. By cold forging,the maximum relative density of all the types o{ W skeletons can reach 81%, and among them W skeleton com- pacted with medium-grained powders has the greatest relative density. The W-10Cu composite materials with dense and uniform microstructure can be prepared by high velocity compaction-cold forging-copper in- filtration with three types of powders and they can also meet the performance requirement for electronic packaging materials. Keywords ： W-10Cu ; W powders ; particle size; single sample weight; W skeleton; electronic packing

Abatract： Characteristics and the architectural performance of titanium and its alloys are introduced, focusing on the examples of their applications in the buildings. Current development and existing problems are also summarized of titanium and its alloys as building materials in China, and the future development is pointed out. Keywords ： titanium and its alloy ; building material ; architectural performance ; current application ; prospect

The energy band structures, density of electronic states and absorption spectra of Al-doped, F-doped and Al-F co-doped anatase TiO2 were calculated using the first-principle plane wave ultra-soft pseudo-potential method based on the density functional theory. The results indicate that the band gaps of all the doped TiO2 decrease to different extent,and that of Al-doped TiO2 decreases most obviously. All the doped anatase TiO2 show blue shift of absorption edge at different level,and among them the blue shift of F-doped TiO2 is the maximum. In visible light region, there is notable increase of absorptivity of F-doped TiO2 and the absorptivity of Al-doped TiO2 is moderately increased, while the absorptivity of A1-F codoped TiO2 is not increased.