The development of large diameter, non magnetic WC Ni carbide dies has been described.The results show that the content and distribution of carbon have the greatest influence on non magnetic alloy.Careful carbon control during degumming is the key to the production of large non magnetic carbide dies.

Study is made of two step carbonization for the production of fine grained Ta carbide. The main factors affecting the product particle size and quality have been investigated.The powder preparation by cemented carbide lined ball mill (use cemented carbide balls as medium),instead of the high capacity pulverizers,will result in smaller particle size and lower Fe content. The Ta carbide from the serial production with the new technological parameters features finer particle size and lower impurity content.The product's quality is satisfactory for the cemented carbide industry.

Experiments and research have been carried out on the electric parameters of EDM of cemented carbide dies, the tool electrode materials and its size calculation Analysis is made of the factors affecting the EDM and the influence of the EDM on the service life of the dies. The paper points out that it is necessary to use CAD/CAM for shape complicated tool electrodes machining;and NC EDM can be used for shape complicated dies.

The paper describes the performance of double cone vacuum driers,and theoritically proves the importance and features of the said equipment in the production of cemented carbide powder.The practical operation has demonstrated its reliability and superiority.

By elementary analysis,UV,1R,MS and H NMR,the structure of nipensamide is obtained as N(4 nitro phenyl group) 5 chloro samide.

Study of the micro defects of DGJW40 steel bonded WC carbide made by a new process showed that this process was better than the existing compacting sintering methods in respect of the alloy's compactness,hole cleanliness,free carbon content and segregation of hard phase in the alloy.

China's cemented carbide industry still lags behind. In the near future (2001～2005),enterprise scientific and technical development and scientific achievment and commercia lization should be expedited in combination with the enterprise restructuring in order to make better development.Suggestions are presented.

This paper presents the results of preparation and sintering of yttria doped ceria powder,and describes the effects of main technical parameters on its properties.

Preliminary analysis is made of the present status and prospect of China's tungsten industry To vitalize its development it is necessary to strengthen the management, deepen the reform,restructure the enterprises, change the operation way and rely on the scientific and technical progress.

This paper emphatically introduces the principle,process and utilization of technics of SHS fabrictaing powder,SHS pressing,SHS melting and casting, SHS coating and SHS welding.