The cast Al-Si alloy ZL101 was prepared by metal model casting process with rare earth element Nd as the modificator.The effects of modification duration and remelting times on the microstructure and mechanical properties of the alloy were investigated by OM,SEM,Brinell hardness tester and electronic universal testing machine.The results show that Nd has a good modification effect on ZL101 alloy,and the effect is of long-lasting and remelting properties.After the alloy is modified for 6 h and remelted by 4 times,its eutectic silicon structure is still in modification state of small slices,and its hardness and tensile properties are not significantly affected.All the tensile specimens of the alloys with different modification duration and different remelting times show cleavage fracture.

Research was made on the changes of mechanical properties of the binder phase and the whole alloy during heat treatment of the WC-8.4Co coarse-grained cemented carbide by nano indentation and high load HV test.The results show that heat treatment can improve hardness of the whole alloy by improving hardness of the binder phase,and meanwhile improve Palmqvist fracture toughness of the whole alloy.

The effects of TaC and Y2O3 addition by different dosage on microstructure and properties of ultrafine YG6 cemented carbides were studied based on the unchanged composition and content of the original Cr3C2/VC grain growth compound inhibitor.The results show that TaC can significantly inhibit YG6 grain growth.The YG6 alloy with 0.1%TaC prepared by pressure sintering at 1 380 ℃ has the maximum density,hardness and flexural strength of 99.88%,HRA 93.8 and 1 800 MPa,respectively.The addition of 0.1%Y2O3 can also inhibit YG6 grain growth yet without obvious effect on the other aspects of the alloy.

Basic design is made on the centralized purification and circulation process of cemented carbide grinding fluid.The selection of the main equipment and automatic control system is studied.The application of the PE sintered micro-filtration membrane filtration system supported by PLC control can assure the cemented carbide grinding quality,reduce the waste fluid discharge and improve the economic efficiency of grinding operation.

Bismuth smelting converter operation and conventional flue gas treatment processes are briefly introduced,and application of the related energy-saving measures are analyzed.The advantages and disadvantages are compared of the two energy-saving measures of dilute oxygen combustion and waste heat recovery from the flue gas.The characteristics of waste heat boiler design for bismuth melting converter are described.

The strength of cold-bound pellets of carbon-dosing Nb-Fe associated ore was studied using polyvinyl alcohol as the binder.The influences of carbon to oxygen ratio in pellets,compacting pressure,binder concentration and drying temperature on the strength of green and roasted pellets were investigated.The results show that the strength of both dry and wet pellets is maximum at carbon to oxygen ratio 1.0,compacting pressure 15 MPa,binder concentration 3%,roasting temperature 100 ℃.

Combustion-Infrared absorption method is introduced to simultaneously determine carbon and sulfur content in corrosion product of uranium-niobium alloy with LECO CS—444 carbon and sulfur analyzer.The suitable parameters were obtained by carbon and sulfur determination experiments on the synthetic samples of known carbon content.Iron scrap and tungsten particle are selected as a mixed flux.When the sample quantity is 0.150 g,the optimal dosages of iron scrap and tungsten particle are 0.050 g and 1.500 g,respectively.The sulfur detection limit of the said method is 3.6 μg/g.RSD of carbon and sulfur measured values are ≤3.0% and ≤15%,respectively.Standard recovery of carbon and sulfur are 98%~111% and 92%~102%,respectively.

The impurities of tantalum powder were determined by inductively coupled plasma mass spectrometry.Instrument working condition,sample preparation,sample analysis model,matrix concentration,precision,recovery and so on were studied.The results show that the method has the advantages of high accuracy and precision.RSD of the determined values for impurity content is 1.64%~15.99%,and the recovery of standard addition is 92%~128%,which can meet the analysis requirement of tantalum powder.

厦门市昱昌机械有限公司一直致力于硬质合金生产设备的研发与改进,自成立以来业绩不断攀升,短短五个年头已为全球一百多家大中型合金生产企业成功实施生产线,并自主开发十余项专利。公司目前已通过ISO9001∶2008质量体系认证,产品质量精益求精,

湖南稀土金属材料研究院始建于1958年，为国有独资科技型企业，是我国最早从事稀土材料应用研究与开发的单位，是军工稀土新材料研制开发的配套单位。该院已通过军品科研生产许可认证和ISO9001中国质量认证。