The properties(phase, particle size. etc. ) of ZrO2-Y2O3ultrafine powder prepared by coprecipitation are studied using the techniques of XRD, DTA, TEM, SEM, etc. The composition, density and microstructure of the sintered compacts are analyzed together with discussion of effects of dispersant, concentration of salt solution,pH, ignition temperature on thecr sintering behavior. Try is made on dispersant instead of absolute ethyl alcohol to dewater to control the powder agglomeration. Optimum conditions for production of ultrafine powder are given with obtaining 20nm ZrO2-Y2O3 ultrafine powder.

This paper briefly introduces the common feature of the SHS process and the SHS's materials; reveals the effects of initial temperature, fast cooling, additives and other factors on microstructure of SHSTiC: analyzes the SHSTiC crystal with discussion about mechanisms of the synthesis and the structure formation.

Molybdenum powders have been made by directly reducing of ammonium molybdate and three-step reduction of ammonium molybdate. The rules of phase transformation taking place during reduction have been investigated by X-ray diffraction analysis and the effects of unstable phase of Mo4O11 on the reduction of molybdenum have also been discussed.

Sintering is aimed to obtain pore-free, near-theoritical density products under the high temperature. But for doped W during sintering, suitable potassium bubbles should be formed to stablize the fine pores so ao to make W wires to have large high-temperature creep strength, and impurities and useless dopant should also be removed simultaneously.The study shows that optimum density of W bars can be obtained under suitable sintering conditions.

The paper briefly described the isostatic pressing process for large-size thin-walled holey carbide cylinder. Mechanical processing methods and vacuum sintering principle for the semi-finished product are also desertbed.

Overall inspection and analysis are made of the structure of WC-TiC-Co double-phase alloys. sintered at different temperatures.Cutting tests are carried out on their related tips. The results show that regardless of the sintering temperature, free WC phases are found in all the double-phase alloys made from WC-TiC 70: 30 by mass saturated solid solution and Co powder. Its relative amount varies inversely with the sintering temperature, while the grain size of the carbide varies directly. The cutting life of the specimen sintered at 1480℃ is the longest.

The paper describes the production method of large-intensity, corrosion-proof and wearable Ti holey tubos from Ti scraps by the means of hydrogenation-dehydrogenation P/M process and heat-diffusion surface treatment. The application of the said tubes is also described.

A new-type electrolytic cell is designed, in which the technology for the recovery of cemented scrap is studied. The results show that the anode passivation can be decreased through the mechanical force of the drum anode, and the current efficiency can be improved.

The paper describes the features of EPMA method and its applications to microanalysis of W-Ni-Fe alloy fractures and microstructures. In the first case, it details the preparation of fracture sample, defect observation and major fracturing type in the second,it details the proparation of polished microsection, and determination of the binding phase constituents, (NiFe)6W6C carbide phase and W grain size.

Use of spectrophotometry with several wave lengths in mixed complex system with 5-Br-PADAP developer to determine Nb and Ta from W concentrate and cassiterite can make the determination fast, accurate and sensitive with relative standard deviation 0. 021 (n= 16). The paper deals with this method.