Vacuum electron beam butt welding was carried out on 3mm thick TaW12 alloy sheets,and then the welded sheet was successively thinned to 2mm and 1.5mm by cold rolling,exhibiting good cold workability of the electron beam weld of TaW12 alloy.Tensile test results show that the tensile strength of the alloy can only reach 699.65～721MPa by simple electron beam welding with 9.38%～13.15%elongation.However,the tensile strength of the machined weld of 1.5 mm thick sheets can be up to 934 MPa,about 93.8%～94.7%tensile strength of 1.5mm thick cold-rolled substrate,and its elongation reaches 8.0%～9.0%.And all the weld tensile samples fracture along the weld center.The cold-rolled electron beam weld has higher strength and plasticity,attributed to weld microstructure refinement and pore decrease caused by cold rolling.

Research on the mechanical properties of Ti-Mo alloy was carried out during hydrogen absorption,and test data of mechanical properties of alloy microstructure were obtained,reflecting its characteristics of elastic and plastic deformation in microscopic field.The results show that the average value of Vickers microhardness HV_（0.5） of Ti-Mo alloy is 332 before hydrogen absorption and 419 after hydrogen absorption with the test force of 4.903 N.The compressive strength of the alloy is higher than 1 730 MPa either before or after hydrogen absorption,and the maximum load force in the test is 50 kN.The change of mechanical properties of Ti-Mo alloy during hydrogen absorption is caused by its phase transformation.

Ti（C_（0.7）N_（0.3））-WC-Mo_2C-TaC-Fe/Co/Ni series cermets were fabricated by low pressure sintering.The effects were investigated of Fe content on microstructure,phase composition and mechanical properties of the Ti（C,N）-based cermets.The results show that with the increase of Fe content,the volume fraction increases of the hard phase with white core-grey rim structure.In addition,a lot of M_（12）C-typeηphase transforms to M_（6）N-type brittle phase during solid-state sintering,and therefore higher Fe content can promote formation of the brittle phase in the cermets.The results of mechanical tests show that appropriate Fe substitution for Ni can obviously improve the fracture toughness and hardness of Ti（C,N）-based cermets,firstly increasing and then decreasing with the increase of Fe content.When Fe content is 2%,the cermet has the maximum hardness of 1 642 MPa and fracture toughness of 10.63 MPa·m1/2,higher than the cermet without Fe by 96 MPa and 11.3%,respectively.However,adding excessive Fe will greatly worsen the mechanical properties of the cermets,mainly due to the increase of M_6N-type brittle phase content in the cermet with high Fe content.

The effects were investigated of melt-spinning velocity on microstructure and hydrogen storage properties of 40Ti-40V-10Cr-10 Mn.The phase analysis shows that the original sample consists of V-based solid solution with body centered structure（BCC phase）.The melt-spun samples at 10 m/s and 30 m/s consist of BCC phase and C14-Laves phase.The melt-spun sample at 20m/s consists of BCC phase and C15-Laves phase.Kinetic mechanism research shows that hydrogen absorption kinetic process can be described by chemical reaction mechanism for the original sample and melt-spun samples at 10m/s and 30m/s and described by 3-D diffusion mechanism for the melt-spun sample at 20m/s.Moreover,with the increase of melt-spinning velocity,hydrogen absorption capacity of the sample at room temperature decreases at first and then increases,getting the minimum at 20 m/s.All the melt-spun samples have higher hydrogen desorption capacity at room temperature than the original sample,and the melt-spun sample at 10 m/s has the maximum with improved hydrogen absorption and desorption hysteresis.With melt-spinning velocity increasing,hydrogen desorption capacity of the sample at 373 Kfirstly decreases and then increases,getting the minimum at 20m/s,and the melt-spun sample at 10m/s and the original sample have the close value.

TiAlN coatings were deposited on the surface of TiCN ceramic tools by ion enhanced magnetron sputtering and evaporating deposition combination source equipments.In order to improve the adhesion of the TiAlN coatings to the substrate,a layer of CrN/Cr film was deposited firstly on TiCN ceramic tools by evaporating deposition.The effects were systematically investigated of CrN/Cr interlayer on microstructure,microhardness,film-substrate adhesion and wear resistance of the coatings by the equipments of X-ray diffractometer,Vickers microhardness tester,Rockwell hardness tester,friction and wear tester and so on.The results show that the CrN/Cr interlayer can effectively improve the adhesion and wear resistance of the coatings.

TbDyFe alloy or DyFe alloy plus terbium metal were used as the raw materials to prepare high performance sintered NdFeB with the similar smelting equipment and process.Comparison was made of thickness distribution,chemical composition,microstructure and magnet properties between the two strip casting products prepared with the same ingredient proportion but in different addition ways.And magnetic properties were investigated of sintered NdFeB magnets with lower terbium content.NdFeB alloy composition was designed according to RE（Pr,Nd,Tb,Dy）_（32.6）M（Fe,Co,Al,Ga,Cu,Nb,Zr）_（bal）B_（1.0）（mass fraction）.The results show that different material addition ways have no obvious effects on the appearance,thickness distribution and microstructure of strip casting products.However,effective terbium components increase by 10.71% in the strip casting product with TbDyFe alloy as the raw material,its magnet coercivity increases by 14.04%,and the remanence slightly decreases.Using TbDyFe alloy with 10% lower terbium dosage of DyFe alloy plus terbium metal,the prepared sintered NdFeB can reach the magnetic property level of the latter,greatly saving the rare earth resources.

Physical properties of Pr-Nd oxide directly affect its electrolysis stability,current efficiency,energy consumption and other technical and economic indexes.Therefore,its physical properties must remain constant and uniform with less volatility.Through comparison of specific surface area,particle size and microstructure and combination with actual production,the effects are analyzed of physical properties of PrNd oxide on its electrolysis,and improvement measures are discussed for its physical properties to meet the requirements of electrolysis.

Some scrap Nd-Fe-B magnets were added in the preparation of sintered Nd-Fe-B,and feed of Nd,Fe,B raw materials were accordingly reduced to prepare the samples by forming,sintering and subsequent processing.Powder size,microstructure and magnetic properties were tested and comparative analysis was done on the Nd-Fe-B samples with and without scrap magnets.The results show that the particle size concentration of the sample with scrap magnets is slightly lower than that of the sample without scrap magnets,and a small portion of particles in the former are of the size over 100μm.However,the two samples have basically consistent microstructure,their magnetic flux decreases together with the increase of aging temperature,and they also have the same thermal variation law.

Denitration experiment was conducted with CO reducing agent and CeO_2-γ-Al_2O_3 catalyst loaded with In and Ag active components of different proportion.The results show that the catalyst with 8%In-8% Ag has the highest catalytic activity,and the conversion rate of NO is over 80% at 300～450 ℃.The effects were studied of the concentration of CO,CO_2 and H_2O on 8% In-8%Ag/CeO_2-γ-A_l2O_3 catalytic activity.The results show that when volume ratio of CO to NO is equal to 1.5,NO removal rate is the highest,and the catalyst also has strong H_2O and CO_2 resistance with strong denitration activity in an environment containing H_2O and CO_2.BET experiment shows that 8%In-8%Ag/CeO_2-γ-Al_2O_3 catalyst has large specific surface area and pore volume.Data from XRD and XPS show that In and Ag exist mainly in the forms of In_2O_3 and Ag_2O in the catalyst,and they strongly interact to promote the formation of AgInO_2,resulting in the high catalytic activity of 8%In-8%Ag/CeO_2-γ-Al_2O_3.

The mixture powders were directly consolidated of SiC particles with different size and industrial pure aluminum by high-pressure torsion（HPT）to prepare SiC_P/Al composites.The volume of the composites was measured with drainage method,and then the density was calculated.Effects of SiC particle size on density and tensile properties of the composites were studied by tensile tests and SEM observation of the tensile fracture.The results show that with the increase of SiC particle size at 200 ℃,both the amount and specific surface area of the particles gradually decrease due to the certain SiC particle content,more large particles are broken by shearing force and weakly bound freshmen interface increases,resulting in both the density and tensile strength of the composites increasing firstly and then decreasing.Meanwhile,the dimples in tensile fracture have increased size with poorer distribution uniformity,the residue particles in the dimple increase,and therefore the composites have weakened ductile fracture characteristics and enhanced brittle fracture characteristics.