Effect of Y Addition on Microstructure and Constituent Phases of Al-Ti-C Master Alloy

Al-Ti-C master alloy was prepared by SHS (Self-propagating High temperature Synthesis)-melting technique. Effect of yttrium addition level on the microstructures of the master alloy was studied by XRD, SEM and EDS. The experimental results show that the addition of 1.0%Y is beneficial to the formation of TiC particles; Al-Ti-C-1.0Y consists of rod-like and blocky TiAl3, TiC, Al3Y and α-Al matrix. Y is found around TiC particles in Al-Ti-C-0.5Y master alloy while blocky (AlTiY) phase appears in Al-Ti-C-1.0Y master alloy. Al3Y with dendritic morphology and small blocky Al2Y except for TiC are found in Al-Ti-C-2-0Y master alloy.     

An analysis of the results of histological and histochemical research on the integumental tissues and the digestive system of nematodes of the suborder Strongylata after the use of anthelmintics

The analysis of the action of various anthelmintics on the integuments and digestive system of Strongylate nematodes indicated that all the used agents caused varying structural disorders. The swelling of the cuticle and its detachment from the subcuticle occurred with the overwhelming majority of the anthelminths on the integuments of the Strongylate nematodes. The digestive system showed an ample epithelial vacuolation in the intestinal wall, as well as swelling and destruction in the mitochondria and endoplasmic reticulum. Almost all the used agent lowered the levels of glycogen and RNA in the tissue of Strongylate nematodes.     

Study on microstructure and mechanical properties of ZL107 alloy added with yttrium

The effects of Y on the microstructure and mechanical properties of ZL107 alloy were investigated using optical microscope, scanning electron microscope (SEM), Brinell hardometer, and MTS 810-22M tensile testing machine in this paper. The results showed that after Y was added to ZL107 alloy, the size of α-Al dendritie reduced, the acicular eutectic Si became short rod-shaped or granular, and the number and size of the blowholes obviously reduced. The mechanical properties of ZL107 alloy firstly increased and then decreased with Y content increasing. When Y content was 0.1 wt.%, the tensile strength and hardness of the alloy were maximum.     

Y2SiO5:Ce3+ particle growth during sol-gel preparation

The phosphor Y2SiO5:Ce3+ was prepared by a sol-gel method and the particle growth process was investigated by XRD, SEM and TEM. After heating at 400 °C, the as-dried gel became a powder composed of mixed phases of polycrystalline Y2O3 and amorphous SiO2. With an increase in temperature, the crystallinity of Y2O3 improved. The sample quickly changed to the pure Y2SiO5 phase when it was heated at 1400 °C for 10 min. SEM indicated that the as-dried gel consisted of large porous particles. At an annealing temperature of higher than 400 °C, the pores in the large particles gradually expanded and grains started to appear. Consequently, the large particles disintegrated into small particles. When the sample was heated at 1400 °C, we obtained fine phosphor particles (around 2 μm) with smooth surfaces. The optimized condition for the preparation of the Y2SiO5:Ce3+ phosphor was to heat at 1400 °C for 2 h.     

Effect of Li+ ions doping on structure and luminescence of (Y,Gd)BO3:Tb3+

The (Y,Gd)BO3:Tb3+ and Li+-doped (Y,Gd)BO3:Tb3+ phosphors were prepared by high temperature solid-state method. The inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray diffraction (XRD), scanning electron microscopy (SEM), and the excitation and emission spectra were used to characterize the samples. The results of ICP-AES and XRD indicated that Li+ ions could enter the (Y,Gd)BO3:Tb3+ lattice and induce the lattice expansion. It could be seen from SEM that the particles were spherical a...     

Oxidation Mechanism of Ni-0.5Y Microcrystal CoatingSputtered by Magnetron at 1 000 ℃

The isothermal and cyclic oxidation behaviors of bulk pure nickel and its Ni-0.5Y microcrystal coating sputtered by magnetron at 1 000 ℃ in air were studied. The scanning electronic microscopy (SEM) and transmission electronic microscopy (TEM) were used to examine the structures of the coating and the NiO oxide films. The laser Raman spectrum was also used to measure the stress level in NiO films formed on bulk nickel and the coating. It is found that the Ni-0.5Y microcrystal coating has lower oxidation rate, and the grain size of NiO formed on Ni-0.5Y coating is also relatively smaller than that formed on bulk nickel. Meanwhile, the compressive stress level of oxide film formed on Ni-0.5Y coating was lower than that formed on bulk nickel, and the high temperature plasticity of oxide film was much improved in coating case. The improvements of anti-oxidation properties of the sputtered Ni-0.5Y coating are due to the microcrystal structure and yttrium.     

钇对EH36船板钢夹杂物特性和拉伸性能的影响

 稀土钇添加到钢中,能够有效变性夹杂物,并能引起拉伸性能的变化。为了研究钇的质量分数对夹杂物变性以及拉伸性能的影响,以EH36船板钢为研究对象,采用扫描电子显微镜、能谱等分析手段,对原始钢以及加入不同量稀土的试样进行夹杂物以及拉伸性能的测试分析。结果表明,稀土元素钇能有效变性夹杂物,将长条状的硫化锰夹杂物或者复合的硫化锰夹杂物变性为以Y Al O为核心的、外圈为稀土氧硫化物的球状夹杂物。对其力学性能检测发现,随着稀土加入量的提高,其抗拉强度和屈服强度显著提高,其中钇质量分数为0.055%的试样具有较好的夹杂物变性形貌和较好的抗拉强度和屈服强度。     

Synthesis and Characterization of Large Surface Area Yttrium Oxide by Precipitation Method

Rareearthoxides(REO)withlargesurfaceareahavehighchemicalreactionactivity ,soitisusedwidelyinthefieldofcatalysis ,SOFC ,advancedce ramicandsoon[1] .Inordertosatisfythedemandofthenewfunctionmaterials ,thepreparationmethodofspecialphysicalpropertyREcompoundneedstobedeveloped .Yttriumoxide ,especiallywithlargesur faceareaisaREOandwidelyusedintheabovefield .Industrially ,yttriumoxideusuallywaspreparedbythermaldecompositionofyttriumoxalateat 80 0～10 0 0℃for 2h .Itssurfaceareaisonly 2～ 4m2 ·…     

复合熔盐法合成Y2O3.Eu3+红色荧光粉

以草酸钇铕(Y2(C2O4)3:Eu3+)为前驱体,采用复合熔盐(NaCl+S+Na2CO3)协助焙烧法合成Y2O3:E.u3+红色荧光粉.利用XRD、SEM、光谱分析等测试和分析荧光粉粒径、颗粒形貌以及发光性能.主要考察复合熔盐配比、用量以及焙烧温度和时间对Y2O3:Eu3+荧光粉发光性能的影响.结果表明,NaCl在...     

Evolution of microstructure and tensile properties of extruded Mg-4Zn-1Y alloy

In order to investigate the effect of extrusion on Mg-4Zn-1Y alloy, microstructure and mechanical properties were analyzed by optical microscopy（OM）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, X-ray diffraction（XRD）, energy dispersive spectrum（EDS） and tensile testing.The results indicated that the microstructure was obviously refined by extrusion and dynamic recrystallization.The second phases were dynamic precipitated and distributed more dispersively through extrusion.W-Phases（Mg3Zn3Y2） were twisted and broken, while I-Phases（Mg3Zn6Y） were spheroidized by deformation.Twin bands were formed to achieve the large deformation and hinder the slip of dislocations effectively to improve tensile properties.The tensile strength and elongation of extruded Mg-4Zn-1Y alloy were 254.94 MPa and 17.9% respectively which were improved greatly compared with those of as-cast alloy.The strengthening mechanisms of the extruded alloy were mainly fine-grain strengthening and distortion strengthening.     

Luminescent Properties of BaMgAl10O17: Eu2+ Phosphors Coated with Y2SiO5

BaMgAl10O17: Eu2 phosphors was prepared by the solid-reaction method.Y2SiO5 was coated uniformly on the surface of phosphor by the surface-coated method, and the luminescent and deterioration properties were discussed.The XRD and SEM results show that Y2SiO5 film is produced on the surface of BAM phosphor.The emission spectrum analysis shows that the peak of the phosphor does not change after coating.The two phosphors were applied to lamps and the deterioration was tested at different ignited time.The keep ratio of luminous flux of the phosphor coated with Y2SiO5 is higher than that of the uncoated phosphor.     

Study on phosphating treatment of aluminum alloy： role of yttrium oxide

Zinc phosphate coatings formed on 6061-Al alloy, after dipping in phosphating solutions containing different amounts of Y2O3(yttrium oxide), were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and electrochemical measurements. Significant variations in the morphology and corrosion resistance afforded by zinc phosphate coating were especially observed as Y2O3 in phosphating solution varied from 0 to 40 mg/L. The addition of Y2O3 changed the initial potential of the interface between aluminum alloy substrate and phosphating solution and increased the number of nucleation sites. The phosphate coating thereby was less porous structure and covered the surface of aluminum alloy completely within short phosphating time. Phosphate coating was mainly composed of Zn3(PO4)2-4H2O (hopeite) and AIPO4(aluminum phosphate). Y2O3, as an additive of phosphatization, accelerated precipitation and refined the gain size of phosphate coating. The corrosion resistance of zinc phosphate coating in 3% NaCl solution was improved as shown by po-larization measurement. In the present research, the optimal amount of Y2O3 was 10-20 mg/L, and the optimal phosphating time was 600 s.     

烧结温度及Y2O3对9Cr-RAFM钢性能的影响

采用粉末冶金技术,以球磨-模压-真空烧结工艺制备2种9Cr-RAFM钢:以0.3%Y2O3(质量分数)为弥散相的ODS 9Cr铁基高温合金和不添加Y2O3的Non-ODS 9Cr铁基高温合金。研究烧结温度及Y2O3对RAFM钢的力学性能和微观组织的影响。研究结果表明:采用球磨-模压-真空烧结工艺制备的ODS合金的综合力学性能高于Non-ODS合金,并且在1 390℃烧结,保温2 h条件下制备的ODS合金具有最佳的综合力学性能(抗拉强度600 MPa,伸长率23.1%)。并对不同球磨时间的合金粉末进行XRD物相分析,用SEM及能谱分析技术研究Y2O3影响RAFM钢的微观组织成分和力学性能的机理。     

稀土Y对气雾化制备PH13-8Mo钢粉末特性的影响

摘要：研究了不同含量的稀土Y对选区激光熔化技术(SLM)用PH13 8Mo钢粉末特性的影响,并通过Thermo-Calc热力学软件、粉体综合特性测试仪、霍尔流速计、激光粒度分析仪、扫描电镜和电子探针等方法对不同Y含量的PH13-8Mo钢粉末特性的变化规律进行研究。结果表明,随着金属粉末中Y含量的增加,金属粉末的松装密度从3.73提高到3.93g/cm3,50g粉末的自由流动时间从25.44减小到25.11s,粉末的流动性变好。同时,PH13 8Mo钢粉末的平均粒径从37.29减小到30.99μm,粉末的粒度分布区间变窄。研究还发现,不含Y的PH13-8Mo钢粉末的组织由树枝晶和等轴晶组成,而Y质量分数为0.080%的PH13 8Mo钢粉末的组织均由等轴晶组成。综上,在PH13.8Mo钢粉末中加入稀土Y,粉末的特性得到优化。     

Low-temperature electrochemical synthesis and characterization of ultrafine Y（OH）_3 and Y_2O_3 nanoparticles

Ultrafine Y(OH)3 nanoparticles were successfully deposited from an additive-free 0.005 mol/L YCl3 low-temperature bath on the steel cathode at the current density of 0.5 mA/cm2 and bath temperature of 10 oC. Heat treatment of the prepared Y(OH)3 nanoparticles at 600 oC in air led to the formation of Y2O3 nanoparticles. Thermal behavior and phase transformation during the heat treatment of Y(OH)3 were investigated by differential scanning calorimetry (DSC) and thermogramimetric analysis (TGA). The morphologies, crystal structures and compositions of the prepared materials were examined by means of scanning and transmission electron microscopy (SEM and TEM) as well as X-ray diffraction (XRD) and FT-IR spectroscopy. The results showed that the prepared Y(OH)3 nanoparticles was essentially amorphous and composed of well dispersed ultrafine particles with size of 4 nm. After heat treatment, the obtained oxide product was well crystallized cubic phase of Y2O3 nanoparticles with the grain size of around 5 nm. It was concluded that low-temperature cathodic electrodeposition offered a facile and feasible way for preparation of ultrafine Y(OH)3 and Y2O3 nanoparticles.     

Effect of rare earth addition on structure and properties of Ni-P coating on SiCp/Al composites

The aim of this work was to improve the properties of Ni-P coating on SiCp/Al composites. The effect of rare earths addition on Ni-P coating structure was investigated by means of scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffractometer (XRD) and electrochemistry methods. The results showed that as Y or La concentration was 0.15 g/L in plating solution, the highest value of deposition rate of Ni-P coating was found. And the structure of the obtained coating was modified...     

Sol-gel synthesis and photoluminescence properties of BaSO_4/Y_2O_3:Eu~(3+) core-shell submicrospheres

Europium-doped nanocrystalline Y2O3 phosphor layers were coated on the surface of preformed submicron BaSO4 spheres via the sol-gel process.The obtained BaSO4/Y2O3:Eu3+ core-shell phosphors were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS) and photoluminescence spectra.The results showed that the obtained BaSO4/Y2O3:Eu3+ core-shell phosphors consisted of well-dispersed submicron spherical particles with na...     

Shape-Controlled Synthesis and Upconversion Luminescence of Y2O3:Yb, Er Microstructures

The Y2O3: Yb3 , Er3 microstructures were fabricated by a hydrothermal method without surfactants.The microstructures structure was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM,KYKY 1000B).The up-conversion luminescence spectra were studied under 978 nm laser diode excitation.In Yb3 and Er3 codoped Y2 O3 microcrystals, the relative intensity of green emission became stronger as the morphology of sample changed from wires to films.     

撞击流-活性炭吸附法制备氧化钇超细粉体

以Y( NO3)3·6H2O和碳酸氢铵为原料,在撞击流反应器中制备碳酸钇,经焙烧得到超细氧化钇粉体.考察了分散剂加入量、反应物摩尔比n( NH4HCO3)/n(Y(NO3)3)、活性碳用量、反应温度、反应时间、搅拌速度以及碳酸钇的焙烧温度和焙烧时间等因素对Y2O3粒径的影响,并用WJL激光粒度仪、TG、XRD和SEM等表征手段对产品进行表征,从而获得制备超细氧化钇的优化工艺条件为:PEG4000的质量为硝酸钇的3％,活性炭用量为0.025 mol·L-1,反应物摩尔比n( NH4HCO3):n(Y( NO3)3)为8:1,反应温度50℃,反应40 min,螺旋桨转速1000 r·min-1,800℃下焙烧1.5h,在此条件下制得球形氧化钇超细粉体,表观粒径小于0.5μm.