The nitriding treatment process of Sm-Fe melt-spinning alloy was researched through XRD,SEM and other means.The results show that Sm-Fe melt-spinning ribbons after nitriding are mainly composed of Sm2 Fe17 Nx,α-Fe,Fe2 O3 and Sm2 O3.After nitriding,Sm-Fe melt-spinning ribbons containing noncrystal partially crystallize,but the crystallinity is relatively low or the grains are small,not excessively grown and almost maintaining the grain size of melt-spinning ribbons.There are clearly visible fine grains scattering in the roll surface after nitriding,and the maximum grain size is about 5μm.The white stuff containing nitrides is distributed in disorder at the boundary of spherical particles on the free surface,and the greater the melt-spinning speed,the more the white stuff precipitated in the Sm-Fe ribbons.

The microstructure of newγ-TiAl alloy sheet before and after rolling was investigated as well as its tensile properties after rolling.The results show that the forged microstructure before rolling mainly containsγphase,α2 phase and a certain amount of B2/βphase.After rolling,the coarse lamellar microstructure decreases and recrystallized isometricγgrains increase.The lamellar clusters are elongated along the rolling direction,and their broken degree is related to rolling deformation.The number of B2/βphase is significantly reduced due to high temperature rolling.After three cycles of heat treatment in the（γ＋α2）phase zone,the alloy lamellar microstructure increases,lamellar space decreases,and the microstructure is significantly refined.The high-temperature tensile plasticity of the sheet is relatively high,and its high-temperature tensile fracture mainly has the mixed features of translamellar facture,interlamellar facture and transgrain facture.

The industrial grade lithium carbonate was transformed into battery grade lithium carbonate by hydrogenation decomposition.The main method of Ca and Mg impurity removal is the combination of pretreatment before hydrogenation and treatment of hydrogenation decomposition.The results show that adding the complexing agent nitrilotriacetic acid with 6 times the total content of cationic impurities during the pretreatment before hydrogenation can effectively remove Ca and Mg from industrial lithium carbonate at 25℃,and the removal rate is 65%.Adding EDTA with 6 times the total content of cationic impurities to the hydrogenated slurry during hydrogenation decomposition,the impurity removal efficiency is over 98%.After the two-stage reactions of pretreatment before hydrogenation and treatment of hydrogen decomposition,Ca and Mg impurities can be reduced below the industry standard of battery grade lithium carbonate,and the Ca and Mg contents in the obtained lithium carbonate product are 0.000 5%and 0.001 4%,respectively.

The effects of annealing temperature on metallographic microstructure,deformation texture,contractile strain ratio（CSR）and Kearns coefficient Frof the finished Zr-4 zirconium alloy were studied.When the finished tube is annealed for stress relief at 450~500 ℃,the tube is in the recovery stage,and this process can not weaken deformation texture formed by crystal surface sliding due to metal deformation.Compared with the rolled tube,CSR value of the annealed tube at 450~500 ℃ has no significant change,and its Frvalue slightly increases with the increase of annealing temperature.At the annealing temperature of 500~530℃,the zirconium alloy tube is in the transition zone between the recovery stage and the recrystallization stage,and most of deformation texture is transformed into annealed texture,resulting in a sharp increase of Frvalue and CSR value.At the annealing temperature of 530~560 ℃,the zirconium alloy tube is in the stage of recrystallization,its microstructure is of equiaxed recrystallized morphology,and the original deformation texture has basically been completely replaced by annealed texture.However,the tube in the stage has not reached complete recrystallization,resulting in a slight increase of Frvalue and CSR value.

Diamond coatings with different carbon source concentrations were deposited on the surface of cemented carbide ball-end milling tool by hot filament chemical vapor deposition（HFCVD）.The effects were studied of carbon source concentration on the microstructure of diamond coatings and cutting performance of the coated tools.The surface morphology,composition and grain orientation of diamond coatings on tool surface were analyzed by scanning electron microscope,Raman spectrometer and X-ray diffractometer.The machining experiments of stone were carried out with the prepared diamond-coated milling tools.The results show that compared with the carbon source concentrations of 2% and 3%,the diamond coating prepared with 1% carbon source concentration has larger grain size and complete micron-size diamond crystal form.There are a large amount of nanodiamond grains in the diamond coating prepared with 3% carbon source concentration.The diamond-coated tool with 3%carbon has the largest flank wear loss,while the diamond-coated tool with 1% carbon source concentration has high coating-matrix bonding force,the minimal flank wear loss and the longest cutting life,and its coating doesn＇t significantly flake.

The surface of WC-Co cemented carbide was ablated by ultrashort laser pulse with different laser flux,to remove part of alloy surface material and form new surface.The influences of laser flux on surface quality of the ablated alloy were analyzed from the aspects of surface roughness,residual stress and microhardness.The results show that with the increase of laser flux,surface roughness of the ablated cemented carbide gradually increases,compressive residual stress decreases at first and then increases,and the microhardness is basically unchanged.During the laser machining process,there are irregular micropores along laser trace on alloy surface,and the number of micropores increases with the increase of the laser flux.

The extraction properties and mechanism of three different extraction systems （P350, P507 and P20：l） for P and Sc were studied. Based on comparison, P204-TBP-kerosene system is the best extraction system for separation of Sc and Pb. The ideal organic phase composition is 25% P204＋4% TBP＋ 71% kerosene, and the suitable feed liquid acidity is 5.4 mol/L. Under the above conditions, Sc extraction rate is 98.78% and P extraction rate is 20.99%. P204 extraction system is suitable for a wide range of feed liquid acidity and P content,and the recovered products can be used directly as a raw material into a high-purity scandium oxide production line. This method has simple and economical process and high recovery rate with the value of popularization and application.

Magnesium chloride and calcium chloride were used to co-precipitate silicon and phosphorus from sodium vanadate solution. The effects of precipitant dosage, solution pH value, purification temperature and time on silicon and phosphorus removal were investigated. The optimum process conditions are as follows： cMg∶（cSi＋cP）=1.3,cCa∶（cSi＋cP）=0.4,pH value of 9. 5,reaction duration of 3 h and temperature of 80 ℃. Under these conditions,the precipitation rates of silicon and phosphorous reach 95.67 % and 88.01 %, respectively,while the precipitation rate of vanadium is only 3.72%. The above method has excellent tech- nical indexes and broad prospects for industrial applications.

The zinc smelting process of oxygen pressure leaching of zinc sulfide concentrate is introduced, the enrichment degree of Ge in the process is analyzed, and the typical technological flowsheet is shown. The oxygen pressure leaching process of zinc sulfide concentrate can enhance the recovery of Ge associated in zinc sulfide concentrate. Ge leaching rate in the above process is high,and high-grade germanium-rich slag can be obtained from the leaching solution by neutralization precipitation or replacement method. In production practice,the leaching rate of Ge can reach 95% and the recovery rate of Ge can reach 75% ,and Ge can be enriched by about 50 times in the replacement residue.

NiCrWCAl alloy coatings with different aluminum contents were fabricated on Q235 steel sub- strate by argon arc cladding technology. The microstructure and properties of cladding coatings were investigated by using inverted microscope, X-ray diffractometer, hardness tester and electrochemical workstation. The results show that the fabricated NiCrWCAl alloy coatings have refined grains,uniformly dispers- ed fine precipitates and compact microstructure with the increase of the aluminum content in a certain range. The cladding coatings mainly consist of fcc-structure γ-Ni solid solution, γ′-Ni3A1 phase, bcc-structure β-NiAl phase,and Cr7 C3 and WC hard phases. As the aluminum content increased, the average hard- ness of cladding coatings firstly increases and then decreases. The microhardness distribution of the clad- ding coating is ideal with 7% aluminum content,and its average HV0.2 value is 550. After addition of alu- minum element, NiCrWC alloy coatings have more positive corrosion potential, and the corrosion resistance of cladding coatings gradually intensifies with aluminum content increasing. When the aluminum content is 7 % ,the cladding coating displays the lowest corrosion rate and excellent corrosion resistance with a corro- sion current density （icon） of 0. 872 μA/cm2and a polarization resistance （Rp） of 113.7 kΩ· cm2.