Vanadium and aluminum ing of mixture of （NH4）2SO4 and were extracted from vanadium-containing carbonaceous shale by roast- carbonaceous shale dust-cinder from fluid bed boiler and leaching of the calcine with dilute sulphuric acid. The effect of the dosage of （NH4）2SO4 ,mixing time,calcination temper- ature and roasting time on leaching rates of vanadium and aluminum were studied. Under the optimized conditions,the leaching rates of vanadium and aluminum reach 88%and 95%, respectively. V2O5 and Al2O3 with standard quality can be extracted from leaching solution with conventional process. The process provides a new solution to mass commercialization of Vanadium extraction from vanadium-containing car- bonaceous shale for advantages of easily-controlled conditions and easily-realized roasting equipments.

Principles and the latest development of preparation processes of high purity tungsten are summa- rized. Both chemical purification methods and physical purification methods are emphatically reviewed, the former covers precipitation separation, solvent extraction and ion exchange, and the latter covers vacuum degassing, vacuum distillation and zone melting. Besides, chemical vapor deposition method is briefly intro- duced, and development trend of high purity tungsten preparation research is pointed out.

The preparation methods including vacuum melting, vacuum distillation, zone melting, electro-re- fining,solid electro-migration and combination method, and evaluation methods of high-purity rare-earth metals are summarized. The existing problems in the respect of domestic research of high-purity rare-earth metals and its future development trend are also presented.

Development process of titanium white production technologies in China is reviewed. The two main technologies of titanium white production are comprehensively compared. And the development trendof titanium white production technologies is pointed out.

The technology is introduced for yttrium-cerium phosphate production with ReCl3 solution as the raw material and phosphoric acid as the precipitation agent. The influencing factors were investigated on the rare earth recovery and yttrium-cerium phosphate medium diameter, and the optimal technological con- ditions were determined. The results show that when the precipitation temperature is about 80 ℃ and the phosphoric acid concentration in the precipitated solution is about 0.12 mol/L, the rare earth recovery is higher. The yttrium-cerium phosphate product can be produced in a certain range of medium diameter, by controlling of single reactor output and appropriate stirring. By proper control of technological conditions, the yttrium-cerium phosphate product with a medium diameter of 3-10μm can be obtained in mass pro duction,and the rare earth recovery is over 90%.

The binary rare earth sulfides were synthesized by solvothermal method, with DDTC as sulfur source and rare earth nitrate as rare earth source, and ethanol as solvent. Their microstructures and mor- phologies were characterized by XRD, SEM and FTIR, and solvothemal synthesis conditions were optimized with Y2 S3 and Pr2 S3 as examples. The results indicate that the binary rare earth sulfides synthesized with solvothermal method have high crystallization degree. Both 8m2S3 and Yb2S3 are of high purity,but there are some sulfur impurities in Y2 S3 and Pr2S3. The binary rare earth sulfides with smaller particle size and lager specific surface area can be obtained by increasing reaction temperature and time.

The effect of Gd content on corrosion resistance of Mg-Gd-Y-Sm-Zr rare earth magnesium alloys was investigated by weight loss method. The microstrueture and corrosion morphology of the alloys were observed by optical microscope （OM） and scanning electron microscope （SEM）. And the alloys and their corrosion products were analyzed by XRD. The results show that after heat treatment, Mg-Gd-Y-Sm-Zr rare earth magnesium alloys are consisted of primary α-Mg matrix and precipitated phases of MgsGd and Mg24 Ys. With the increase of Gd content, the alloy grains become finer and the precipitated phases gradual- ly increase. The alloy corrosion rate increases at first and then decreases as Gd content increases, and Mg- 12Gd-2Y-1Sm-0.5Zr alloy has the best corrosion resistance.

TZM alloy was prepared by powder metallurgy,and the effects of Ti and Zr adding forms on its microstructure and morphology, Vickers hardness, high temperature deformation resistance were investiga- ted. The results indicate that the addition of Ti and Zr elements results in lots of Ti and Zr oxides and sim- ple substances in TZM alloy, effectively hindering dislocation motion and improving alloy intensity. TZM alloy with Ti and Zr added in the form of TiH2-Zr has dispersed and uniform second phase and the greatest high temperature deformation resistance.

Annealing was done on TaWl2 alloy tensile samples at 1 340-1 430 ℃ ,and investigations were made on the rule of change of their room temperature mechanical properties with the annealing mode. The microstructure and fracture morphology of the annealed samples were observed by metallurgical micro- scope and scanning electron microscope. The results show that the annealed sample at 1 340 ℃ has tensile strength of 730 MPa and yield strength of 660 MPa. And the annealed sample at 1 430 ℃ has tensile strength of 660 MPa and yield strength of 550 MPa. The strength of the alloy decreases with annealing temperature increasing,but remains at a high level. The elongation rate of the alloy increases from 32% to 45% with the increase of annealing temperature, indicating obviously improved plasticity. The annealed tensile sample at 1 430 ℃ has obvious necking phenomenon,and its shrinkage rate reaches the maximum value. The final suitable annealing mode is （1 400-1 430 ℃）×2 h for TAW12 alloy.

The multi element high entropy alloys Al2 CrFeNiCox CuTi （x = 0. 5,1. 0,1. 5,2. 0） with different Co contents were prepared using laser cladding method. Electrochemical performances of the alloys were tested in 1 mol/L NaC1 solution and 0.5 mol/L H2SO4 solution,and the corresponding polarization curves were drawn. The results show that the high entropy alloys are columnar and equiaxed crystals, with the phase structure of fcc and hcc. The phase of fcc increases gradually with the increase of Co content in the alloys, enhancing intergranular corrosion and then reducing corrosion resistance of the alloys.