Analysis and discussion is made of the major concerns such as grain size,oxygen content and density controls in the mechanical alloying for fabrication of superfine or nanosized CuCr contact materials.Furthermore,a new idea of normal vacuum sintering technique with the addition of high-property grain growth inhibitor to fabricate high-property CuCr contact materials at lower cost.

Description is made of the development and utilization of Ni lean ore resource and mine production in Jinchuan Mine.Detailed description is made of the significance of the development and utilization of lean ore resource in the mine.

A new method for metallurgical thermodynamic equilibrium calculation in which the function of mathematical calculation of EXCEL is used,is provided in this paper.This method characterized by swift, accurate and simple operation,avoids the inconvenient process of solving multiply equitation with routine methods and can directly draw the thermodynamic equilibrium diagram in the current EXCEL worksheet.So this method is practical for thermodynamic equilibrium calculation and the drawing of equilibrium diagram of metallurgical process.

Based on the production practice, analysis is made of BeO loss distribution and metal recovery influence factors during industrial BeO production.The improvement methods and measures are presented.

The article describes the production method, material requirement,process flowsheet,technical quota of FeNb.Based on the actual production,analysis is made of theinfluence of furnace charge,burdening ratio and feed rate on Nb recovery in FeNb alloy production.

β-phase content of the α+β type Ti-6Al-4V sheet can be increased through deuterium treatment under 0.1 MPa hydrogen atmosphere.And the alloy grain size can be reduced.The alloy with deuterium absorption 0.5% (mass/percentage) is stripped at 973K temperature and grain size is reduced from initial 20 micro meter down to 1～3 micro meter when the stripping temperature goes down to 873k to obtain fine and super-fine Ti alloy.The testing results showed that the alloy's mechanical property such as super-plastic elongation,etc is increased with the reduction of the grain size.

Study is made of removal of organic matter from industrial H_2TaF_7 solution by active carbon in order to reduce carbon content in K_2TaF_7 crystal.The test results showed that active carbon can reduce COD value in H_2TaF_7 solution,consequently reduce carbon content in K_2TaF_7 crystal from 0.002 5%～0.003 0% to 0.001.0 %～0.001 5%, and the percloration & absorption factor reached 70In addition,there is linear relationship between COD value in H_2TaF_7 solution and carbon content in K_2TaF_7 crystal,the carbon content in K_2TaF_7 crystal decreases with the decreasing of COD value in H_2TaF_7 solution.When COD value is lower than 8 mg/L,carbon content in K_2TaF_7 crystal would be reduced down to less than 0.001 5%.

Study is made of the effects and effecting mechanisms of a new type of grain growth inhibitor on vacuum sintering behavior of nanometer cemented carbide.The results show that the new grain-growth inhibitor can improve sintering densification process.The addition of the new grain-growth inhibitor into traditional transitional element carbides,resulteding composite inhibitors,which are much more effective and can induce oriented WC grain growth obviously during sintering.For WC-10Co-0.8VC/Cr_3C_2 powders with 0.1% mass content of the new additive,the density of 14.48 g/cm^3 can be achieved after sintering at 1 375 ℃ for 30 min, corresponding to the grain size of 160 nm and the micro-hardness of 2 150 MPa.

Study and analysis is made of the transformation of the microstructure and the hardness of WC/steel composite material under different heat-treatment conditions.And effect of the heat-treatment temperature on high-temperature wearing character is also investigated.The results showed WC/steel composites material has good high-temperature wearing character when quenching at 1 050 ℃ and tempering at 480 ℃ and 640 ℃.