Volume 36,Issue 2,2007 Table of Contents
2007, 36(2):189-193.
Abstract:
利用放电等离子烧结（SPS）技术，原位制备Ti2AlC／TiAl复合材料，并对其进行多步热处理，研究增强相Ti2AlC和微量元素B对Ti2AlC／TiAl复合材料热处理组织的细化作用。研究发现，在热处理过程中，Ti2AlC和B能够显著抑制TiAl基体中γ晶粒和α2／γ层片晶团的长大，有效地细化Ti2AlC／TiAl复合材料的热处理组织。显微组织的细化能够显著强韧化复合材料，其中经1390℃热处理的复合材料的弯曲强度达到957．9MPa，断裂韧性达到20．73MPa·m^1/2。
利用放电等离子烧结（SPS）技术，原位制备Ti2AlC／TiAl复合材料，并对其进行多步热处理，研究增强相Ti2AlC和微量元素B对Ti2AlC／TiAl复合材料热处理组织的细化作用。研究发现，在热处理过程中，Ti2AlC和B能够显著抑制TiAl基体中γ晶粒和α2／γ层片晶团的长大，有效地细化Ti2AlC／TiAl复合材料的热处理组织。显微组织的细化能够显著强韧化复合材料，其中经1390℃热处理的复合材料的弯曲强度达到957．9MPa，断裂韧性达到20．73MPa·m^1/2。
2007, 36(2):194-196.
Abstract:
The distribution of the melt flow field under electromagnetic force and gas bubble floatage is already studied by the numerical simulation method for a 3 kA neodymium electrobath. These results will provide the theoretical foundation for further improving and optimizing the structure of electrobath.
The distribution of the melt flow field under electromagnetic force and gas bubble floatage is already studied by the numerical simulation method for a 3 kA neodymium electrobath. These results will provide the theoretical foundation for further improving and optimizing the structure of electrobath.
2007, 36(2):197-200.
Abstract:
Rare earth metals have distinct influence on hydrogenation,magnetic and catalytic properties of the Pd-rich alloys.Investigation on the most Pd-rich compounds in the Pd-RE systems is significant.In this work,single phase compounds CePd5,PrPd5 and NdPd5 were prepared by a proper smelting and heat treatment.X-ray diffraction was used to determine their structure and lattice parameters.It is found that the most Pd-rich compound in the Pd-Ce system is CePd5 with the hexagonal CaCu5-type structure,and that in the Pd-Pr and Pd-Nd system is PrPd5 and NdPd5 with the orthorhombic SmPt5-type structure,respectively.X-ray diffraction data for the three intermetallic compounds have been reported.Following lattice parameters have been obtained:a=0.5372 nm,c=0.4178 nm for CePd5;a=0.5278 nm,b=0.9239 nm,c=2.575 nm for PrPd5;a=0.5265 nm,b=0.9219 nm,c=2.570 nm for NdPd5.The stoichiometries and the crystal structures of the most Pd-rich compounds in the Pd-RE systems have been compared with those in the Pt-RE systems.
Rare earth metals have distinct influence on hydrogenation,magnetic and catalytic properties of the Pd-rich alloys.Investigation on the most Pd-rich compounds in the Pd-RE systems is significant.In this work,single phase compounds CePd5,PrPd5 and NdPd5 were prepared by a proper smelting and heat treatment.X-ray diffraction was used to determine their structure and lattice parameters.It is found that the most Pd-rich compound in the Pd-Ce system is CePd5 with the hexagonal CaCu5-type structure,and that in the Pd-Pr and Pd-Nd system is PrPd5 and NdPd5 with the orthorhombic SmPt5-type structure,respectively.X-ray diffraction data for the three intermetallic compounds have been reported.Following lattice parameters have been obtained:a=0.5372 nm,c=0.4178 nm for CePd5;a=0.5278 nm,b=0.9239 nm,c=2.575 nm for PrPd5;a=0.5265 nm,b=0.9219 nm,c=2.570 nm for NdPd5.The stoichiometries and the crystal structures of the most Pd-rich compounds in the Pd-RE systems have been compared with those in the Pt-RE systems.
2007, 36(2):201-207.
Abstract:
This paper presents the galvanic corrosion behaviors of AM60 magnesium alloy coupled with variable materials(carbon steel,stainless steel,brass and aluminum alloy) in the outdoor atmosphere of Beijing.The correlations among mass variation,galvanic effect and atmospheric factors for AM60 magnesium alloy coupons were investigated.Surface morphologies were observed by scanning electron microscopy(SEM),and X-ray diffraction(XRD) was used to analyze the crystal corrosion products.The results showed that the AM60 magnesium alloy acted as anodic material when it coupled with tested metals.The arrangement order of galvanic effect from strong to little is carbon steel,brass,stainless steel and aluminum alloy after 12 months exposure in Beijing atmosphere.The atmospheric galvanic effect of magnesium alloys coupled with aluminum alloy is the least among the tested coupled alloys during any testing periods because the effective potential difference of the cathode(AM60) and anode(aluminum alloy) is the least for all of tested coupled alloys.The atmospheric galvanic effects in Beijing compared with other cities indicate that atmospheric environment is most important factor.The atmospheric galvanic effects for magnesium alloys are affected by cathode alloy,testing time,sample acreage and environment condition.And no intact and protective corroded products layer was formed to prevent further corrosion after 1 year exposure.The edge of AM60 coupon suffered harsh galvanic corrosion,which was limited by the existing of thin-film on the coupon surface.The high dust precipitation of Beijing could prolong the time of wetness on metal surface.So,the atmospheric corrosion of AM60 magnesium alloy coupled with different metals could be accelerated.
This paper presents the galvanic corrosion behaviors of AM60 magnesium alloy coupled with variable materials(carbon steel,stainless steel,brass and aluminum alloy) in the outdoor atmosphere of Beijing.The correlations among mass variation,galvanic effect and atmospheric factors for AM60 magnesium alloy coupons were investigated.Surface morphologies were observed by scanning electron microscopy(SEM),and X-ray diffraction(XRD) was used to analyze the crystal corrosion products.The results showed that the AM60 magnesium alloy acted as anodic material when it coupled with tested metals.The arrangement order of galvanic effect from strong to little is carbon steel,brass,stainless steel and aluminum alloy after 12 months exposure in Beijing atmosphere.The atmospheric galvanic effect of magnesium alloys coupled with aluminum alloy is the least among the tested coupled alloys during any testing periods because the effective potential difference of the cathode(AM60) and anode(aluminum alloy) is the least for all of tested coupled alloys.The atmospheric galvanic effects in Beijing compared with other cities indicate that atmospheric environment is most important factor.The atmospheric galvanic effects for magnesium alloys are affected by cathode alloy,testing time,sample acreage and environment condition.And no intact and protective corroded products layer was formed to prevent further corrosion after 1 year exposure.The edge of AM60 coupon suffered harsh galvanic corrosion,which was limited by the existing of thin-film on the coupon surface.The high dust precipitation of Beijing could prolong the time of wetness on metal surface.So,the atmospheric corrosion of AM60 magnesium alloy coupled with different metals could be accelerated.
2007, 36(2):208-210.
Abstract:
When a high frequency alternating current flows through the Co-based amorphous ribbon bended, there is obvious stress-impedance effect due to the stress. A Co-based amorphous ribbon Co66.3Fe3.7Si12B18 annealed with an appropriate pulse current is used in the experiment. The impedance ratio dependence on the bend and the effect of alternating current value and frequency on the stress-impedance of Co-based amorphous ribbon have been studied. The experiment results show that the Co-based amorphous ribbon has obvious stress-impedance effect, and the maximal impedance ratio can reach 25%. The ribbon has negative impedance ratio when the displacement of the end of the elastomer is positive direction, however, it has positive impedance ratio when the displacement is negative direction, but they all increase with the increasing of displacement. The impedance ratio increases firstly until a maximum and then reduces with the increase of frequency at the same displacement. The impedance ratio dependence on the current value also has the same trend.
When a high frequency alternating current flows through the Co-based amorphous ribbon bended, there is obvious stress-impedance effect due to the stress. A Co-based amorphous ribbon Co66.3Fe3.7Si12B18 annealed with an appropriate pulse current is used in the experiment. The impedance ratio dependence on the bend and the effect of alternating current value and frequency on the stress-impedance of Co-based amorphous ribbon have been studied. The experiment results show that the Co-based amorphous ribbon has obvious stress-impedance effect, and the maximal impedance ratio can reach 25%. The ribbon has negative impedance ratio when the displacement of the end of the elastomer is positive direction, however, it has positive impedance ratio when the displacement is negative direction, but they all increase with the increasing of displacement. The impedance ratio increases firstly until a maximum and then reduces with the increase of frequency at the same displacement. The impedance ratio dependence on the current value also has the same trend.
2007, 36(2):211-215.
Abstract:
The defects forming mechanism in the Laser Rapid Forming(LRF) process of titanium and titanium alloy was studied through microscopic analysis methods.The results showed that there were two kinds of defects,porosity and ill bonding in the laser multi-layer cladding.For the LRF titanium and titanium alloy,the porosity was spherical and randomly distributed in samples due to the low loose density of the powders,and the oxygen content wasn't the factor to influence the porosity rate.The ill bonding tended to be irregular shape and generally occurred between the layers and the line boundaries.The laser energy density,overlap and Z-increment ?Z were main process characteristic parameters to influence the ill bonding.
The defects forming mechanism in the Laser Rapid Forming(LRF) process of titanium and titanium alloy was studied through microscopic analysis methods.The results showed that there were two kinds of defects,porosity and ill bonding in the laser multi-layer cladding.For the LRF titanium and titanium alloy,the porosity was spherical and randomly distributed in samples due to the low loose density of the powders,and the oxygen content wasn't the factor to influence the porosity rate.The ill bonding tended to be irregular shape and generally occurred between the layers and the line boundaries.The laser energy density,overlap and Z-increment ?Z were main process characteristic parameters to influence the ill bonding.
2007, 36(2):216-220.
Abstract:
采用微观测试分析方法对沉淀增强型镍基高温合金Rene88DT激光快速成形裂纹产生机理进行了研究。发现裂纹为液化裂纹，具有典型的沿晶开裂特征。激光快速成形过程中，沉积当前层时，已经凝固的前一层沉积层经受再热循环，晶界处的γ／γ′低熔共晶发生液化，在随沉积过程进行而逐渐增大的残余拉伸应力的作用下被拉开，形成液化裂纹。激光成形件组织具有典型的外延柱状生长特点，沉积层底部为近似平行于沉积方向的细长枝晶，其顶部由于热流方向改变枝晶发生转向，在沉积下一层时，道与道之间的搭接区容易存在转向枝晶未熔的区域，因此生长方向偏离沉积方向一定角度的枝晶在搭接区交汇形成晶界，使得该区域成为开裂的敏感区域。柱状枝晶的晶界沿层与层之间具有贯通的渠道，液化裂纹一旦形成就会沿晶界迅速扩展，因此裂纹大体沿道与道之间措接区域发展。
采用微观测试分析方法对沉淀增强型镍基高温合金Rene88DT激光快速成形裂纹产生机理进行了研究。发现裂纹为液化裂纹，具有典型的沿晶开裂特征。激光快速成形过程中，沉积当前层时，已经凝固的前一层沉积层经受再热循环，晶界处的γ／γ′低熔共晶发生液化，在随沉积过程进行而逐渐增大的残余拉伸应力的作用下被拉开，形成液化裂纹。激光成形件组织具有典型的外延柱状生长特点，沉积层底部为近似平行于沉积方向的细长枝晶，其顶部由于热流方向改变枝晶发生转向，在沉积下一层时，道与道之间的搭接区容易存在转向枝晶未熔的区域，因此生长方向偏离沉积方向一定角度的枝晶在搭接区交汇形成晶界，使得该区域成为开裂的敏感区域。柱状枝晶的晶界沿层与层之间具有贯通的渠道，液化裂纹一旦形成就会沿晶界迅速扩展，因此裂纹大体沿道与道之间措接区域发展。
2007, 36(2):221-225.
Abstract:
通过热-机耦合弹塑性模型，采用有限元分析软件MSC.Marc，对纯镁旋锻过程进行了模拟，着重分析了锻模圆锥进料角α对旋锻变形应变场的影响。结果表明：随α增大，各节点变形所需脉冲锻打次数减少，而每次锻打的应变量增加，因而小圆锥进料角有利于低塑性材料的变形：随圆锥进料角α增大，应变沿工件径向分布趋于均匀，且α增大到一阈值αTres后，继续增大不再对应变的径向分部产生影响，在本模拟的工艺条件下。αTres=21°40′：工件外表面应变沿轴向分部呈脉冲似波动，且随α增大，波动的振幅增大：在本模拟的工艺条件下，9°30′≤α≤21°40′是合适的。实验结果与模拟结果吻合较好。
通过热-机耦合弹塑性模型，采用有限元分析软件MSC.Marc，对纯镁旋锻过程进行了模拟，着重分析了锻模圆锥进料角α对旋锻变形应变场的影响。结果表明：随α增大，各节点变形所需脉冲锻打次数减少，而每次锻打的应变量增加，因而小圆锥进料角有利于低塑性材料的变形：随圆锥进料角α增大，应变沿工件径向分布趋于均匀，且α增大到一阈值αTres后，继续增大不再对应变的径向分部产生影响，在本模拟的工艺条件下。αTres=21°40′：工件外表面应变沿轴向分部呈脉冲似波动，且随α增大，波动的振幅增大：在本模拟的工艺条件下，9°30′≤α≤21°40′是合适的。实验结果与模拟结果吻合较好。
2007, 36(2):226-230.
Abstract:
利用机械合金化方法制备了Mg-3Ni-2MnO2氢化物储氢材料，并对其吸放氢动力学性能进行了测试：利用Avrami指数研究了储氢材料吸放氢过程中相转变行为特征，利用形核长大理论建立其本征吸放氢动力学方程，并进行了计算。结果表明：利用机械合金化方法能够制备具有良好吸放氢动力学性能的储氢材料：200℃，2．5MPa条件下需要约65s的时间完成吸氢，吸氢量为6．23％（质量分数），300℃，0．1MPa条件下完成充分的放氢需要约550s的时间。吸氢过程Avrami指数约为0．5，其相变的主要过程为盘状氢化物沿厚度方向的生长：放氢过程中，根据Avrami指数的变化。其相转变特征为形核长大阶段、新相继续稳定长大阶段（无新的晶核形成）。动力学方程计算结果与试验曲线能较好的吻合：温度和压力对吸放氢动力学性能都有影响。
利用机械合金化方法制备了Mg-3Ni-2MnO2氢化物储氢材料，并对其吸放氢动力学性能进行了测试：利用Avrami指数研究了储氢材料吸放氢过程中相转变行为特征，利用形核长大理论建立其本征吸放氢动力学方程，并进行了计算。结果表明：利用机械合金化方法能够制备具有良好吸放氢动力学性能的储氢材料：200℃，2．5MPa条件下需要约65s的时间完成吸氢，吸氢量为6．23％（质量分数），300℃，0．1MPa条件下完成充分的放氢需要约550s的时间。吸氢过程Avrami指数约为0．5，其相变的主要过程为盘状氢化物沿厚度方向的生长：放氢过程中，根据Avrami指数的变化。其相转变特征为形核长大阶段、新相继续稳定长大阶段（无新的晶核形成）。动力学方程计算结果与试验曲线能较好的吻合：温度和压力对吸放氢动力学性能都有影响。
2007, 36(2):231-235.
Abstract:
通过扫描电镜原位拉伸实验，动态跟踪观察了2种非金属夹杂物对FGH95合金裂纹萌生和扩展的影响规律。结果表明，裂纹在夹杂物处萌生，塑性莫来石类夹杂的尖角处，是裂纹萌生的择优位置。在最大正应力和最大剪应力的作用下，裂纹沿与主应力轴垂直或约45°向夹杂内部扩展。当裂纹扩展到基体中之后，呈锯齿状向基体内扩展，但主裂纹所在平面仍与主应力轴垂直，其尖端变形带内有明显的滑移线出现。夹杂物附近基体中的贫γ′相区，断口呈韧性沿晶断裂，而远离夹杂物的基体处则变为穿晶断裂。
通过扫描电镜原位拉伸实验，动态跟踪观察了2种非金属夹杂物对FGH95合金裂纹萌生和扩展的影响规律。结果表明，裂纹在夹杂物处萌生，塑性莫来石类夹杂的尖角处，是裂纹萌生的择优位置。在最大正应力和最大剪应力的作用下，裂纹沿与主应力轴垂直或约45°向夹杂内部扩展。当裂纹扩展到基体中之后，呈锯齿状向基体内扩展，但主裂纹所在平面仍与主应力轴垂直，其尖端变形带内有明显的滑移线出现。夹杂物附近基体中的贫γ′相区，断口呈韧性沿晶断裂，而远离夹杂物的基体处则变为穿晶断裂。
2007, 36(2):236-240.
Abstract:
Bulk amorphous Cu52.5Ti30Zr11.5Ni6(at.%) alloys up to 5 mm in diameter were fabricated by a copper mold casting method.The critical cooling rate was determined to be 126.8 K/s by using the Barandiaran-Colmenero expression.Based upon the Jackson-Hunt relation,the cooling rate for the formation of devitrified structure was also evaluated.In the cooling range of 10 K/s ~ 120 K/s,there exists a mixed microstructure of primary metastable phase and eutectic structure.With further decreasing of cooling rate(below 10K/s),the precipitation of metastable phase was depressed,and the growth mode also deviates from the eutectic mode.
Bulk amorphous Cu52.5Ti30Zr11.5Ni6(at.%) alloys up to 5 mm in diameter were fabricated by a copper mold casting method.The critical cooling rate was determined to be 126.8 K/s by using the Barandiaran-Colmenero expression.Based upon the Jackson-Hunt relation,the cooling rate for the formation of devitrified structure was also evaluated.In the cooling range of 10 K/s ~ 120 K/s,there exists a mixed microstructure of primary metastable phase and eutectic structure.With further decreasing of cooling rate(below 10K/s),the precipitation of metastable phase was depressed,and the growth mode also deviates from the eutectic mode.
2007, 36(2):241-244.
Abstract:
In this paper,the atoms diffusion and growth behavior of intermetallic compounds(IMCs) on the Sn-Ag-Cu/Ni and Sn-Ag-Cu/Cu interfaces under the thermal-shearing cycling condition were investigated.The results showed that two kinds of IMCs,(CuxNi1-x)6Sn5 and(NixCu1-x)Sn3,formed on the Sn-Ag-Cu/Ni interface,but only Cu6Sn5 IMC layer formed on the Sn-Ag-Cu solder and Cu interface under the thermal-shearing condition of 720 cycles.The morphology of(CuxNi1-x)6Sn5 and Cu6Sn5 IMCs varied from scallop-type to planar-type with increasing the thermal-shearing cycling periods,while(NixCu1-x)Sn3 IMC formed surrounding(CuxNi1-x)6Sn5 IMC after 200 cycles.The IMC thickness increased with the increasing of thermal-shearing cycling periods by a role of parabolic growth kinetics,it implied that the IMC growth was controlled by Cu atom diffusion.
In this paper,the atoms diffusion and growth behavior of intermetallic compounds(IMCs) on the Sn-Ag-Cu/Ni and Sn-Ag-Cu/Cu interfaces under the thermal-shearing cycling condition were investigated.The results showed that two kinds of IMCs,(CuxNi1-x)6Sn5 and(NixCu1-x)Sn3,formed on the Sn-Ag-Cu/Ni interface,but only Cu6Sn5 IMC layer formed on the Sn-Ag-Cu solder and Cu interface under the thermal-shearing condition of 720 cycles.The morphology of(CuxNi1-x)6Sn5 and Cu6Sn5 IMCs varied from scallop-type to planar-type with increasing the thermal-shearing cycling periods,while(NixCu1-x)Sn3 IMC formed surrounding(CuxNi1-x)6Sn5 IMC after 200 cycles.The IMC thickness increased with the increasing of thermal-shearing cycling periods by a role of parabolic growth kinetics,it implied that the IMC growth was controlled by Cu atom diffusion.
2007, 36(2):245-249.
Abstract:
In this paper, Ti/IrO2-Ta2O5 anodes with different ratios of IrO2 were prepared by thermolytic decomposition method for sulfate electrolysis. The structure and morphologies of the oxide films were determined by XRD and SEM, respectively. Linear Sweep Voltammetry, Tafel Plot and Cyclic Voltammetry were used to characterize their electrochemical activities of oxygen evolution. Test results show that the iridium and tantalum could form solid solution structure. The mutual solubility between iridium and tantalum is affected by the ratio of Ir/Ta in coating solution and influences the dimension parameters of IrO2 crystals. The finer IrO2 crystallites increase on the coating surface and the electrocatalytic capability of oxygen evolution is strengthened with the increasing of IrO2 content in the coatings. When the content of IrO2 is too high, the coating adhesion and rigidity would decrease which affect electrochemical activity of the anode. The electrochemically active surface area is determined not only by the content of IrO2, but also the structure and morphology of the anode coatings. It is probably due to the existence of proper quantities of inert Ta2O5, resulting in a typical morphology of cracks and solid solution structure. The solid solution structure is helpful to prolong the anode service life. The morphology of cracks could perhaps improve the anode active surface area and the electrocatalytic activity of oxygen evolution.
In this paper, Ti/IrO2-Ta2O5 anodes with different ratios of IrO2 were prepared by thermolytic decomposition method for sulfate electrolysis. The structure and morphologies of the oxide films were determined by XRD and SEM, respectively. Linear Sweep Voltammetry, Tafel Plot and Cyclic Voltammetry were used to characterize their electrochemical activities of oxygen evolution. Test results show that the iridium and tantalum could form solid solution structure. The mutual solubility between iridium and tantalum is affected by the ratio of Ir/Ta in coating solution and influences the dimension parameters of IrO2 crystals. The finer IrO2 crystallites increase on the coating surface and the electrocatalytic capability of oxygen evolution is strengthened with the increasing of IrO2 content in the coatings. When the content of IrO2 is too high, the coating adhesion and rigidity would decrease which affect electrochemical activity of the anode. The electrochemically active surface area is determined not only by the content of IrO2, but also the structure and morphology of the anode coatings. It is probably due to the existence of proper quantities of inert Ta2O5, resulting in a typical morphology of cracks and solid solution structure. The solid solution structure is helpful to prolong the anode service life. The morphology of cracks could perhaps improve the anode active surface area and the electrocatalytic activity of oxygen evolution.
2007, 36(2):250-254.
Abstract:
Ti-Fe alloy nanometer powders with particle size between 5 nm~30 nm were prepared by gas evaporation with arc as a heating source.The formation regularities of the phases and the melting point of the powers were investigated.The results indicate that the as-formed alloy phases in the nanometer powders are different from that in the Ti-Fe equilibrium phase diagram.FCC and TiFe2 phases were easily obtained when the master alloy rich in Fe was evaporated;by contrast,we gained FCC and TiFe phases when the master alloy rich in Ti were evaporated.The relative amount of the FCC phase is always the highest in all the powder samples.As the component of Fe in the master alloy is 53wt%,the relative amount of FeTi phase in the as-prepared powder was the highest among all the samples.A little amount of Ti phase was detected in the nanometer powders only when the Fe10Ti90 master alloy was evaporated due to the formation of the FCC phase.The lattice spacing of d(111) plane of FCC phase increased with the increase of Ti amount in the master alloys,which confirmed the solution of the Ti in the phase.The DSC curves showed that the mean melting points of these nanometer powders were lower than that of the as-formed alloy phases at equilibrium state.
Ti-Fe alloy nanometer powders with particle size between 5 nm~30 nm were prepared by gas evaporation with arc as a heating source.The formation regularities of the phases and the melting point of the powers were investigated.The results indicate that the as-formed alloy phases in the nanometer powders are different from that in the Ti-Fe equilibrium phase diagram.FCC and TiFe2 phases were easily obtained when the master alloy rich in Fe was evaporated;by contrast,we gained FCC and TiFe phases when the master alloy rich in Ti were evaporated.The relative amount of the FCC phase is always the highest in all the powder samples.As the component of Fe in the master alloy is 53wt%,the relative amount of FeTi phase in the as-prepared powder was the highest among all the samples.A little amount of Ti phase was detected in the nanometer powders only when the Fe10Ti90 master alloy was evaporated due to the formation of the FCC phase.The lattice spacing of d(111) plane of FCC phase increased with the increase of Ti amount in the master alloys,which confirmed the solution of the Ti in the phase.The DSC curves showed that the mean melting points of these nanometer powders were lower than that of the as-formed alloy phases at equilibrium state.
2007, 36(2):255-258.
Abstract:
Diamond-like carbon(DLC) films were fabricated on NiTi alloys using plasma immersion ion implantation and deposition(PIIID).The surface morphology and roughness were analyzed by atomic force microscopy(AFM).The film microstructure and hardness were characterized by Raman scattering spectroscopy and nano-indentation system,respectively.The corrosion resistance in Hank's solution was evaluated by mean of potentiodynamic polarization techniques.The surface morphology of the samples was observed using scanning electron microscopy(SEM) after potentiodynamic polarization tests.The Ni ions release from the NiTi alloys was measured by atomic absorption spectroscopy(AAS).It is shown that the roughness and hardness of the NiTi alloys is reduced and increased by DLC film,respectively.The DLC films markedly improve the corrosion resistance of the NiTi alloys and effectively prevent the Ni ions dissolution from the substrate.
Diamond-like carbon(DLC) films were fabricated on NiTi alloys using plasma immersion ion implantation and deposition(PIIID).The surface morphology and roughness were analyzed by atomic force microscopy(AFM).The film microstructure and hardness were characterized by Raman scattering spectroscopy and nano-indentation system,respectively.The corrosion resistance in Hank's solution was evaluated by mean of potentiodynamic polarization techniques.The surface morphology of the samples was observed using scanning electron microscopy(SEM) after potentiodynamic polarization tests.The Ni ions release from the NiTi alloys was measured by atomic absorption spectroscopy(AAS).It is shown that the roughness and hardness of the NiTi alloys is reduced and increased by DLC film,respectively.The DLC films markedly improve the corrosion resistance of the NiTi alloys and effectively prevent the Ni ions dissolution from the substrate.
2007, 36(2):259-263.
Abstract:
开发了Al-K2ZrF6体系熔体反应法合成原位铝基复合材料，采用XRD，SEM和TEM分析了复合材料中相组成、微观组织和界面结构。实验结果表明：合成的增强相为Al3Zr颗粒，常规金属型铸造的复合材料中其尺寸在3μm～4μm左右，一般成聚集态分布，颗粒形貌基本为长方体状：该复合材料经重熔快淬成形后，颗粒尺寸减小，基本为粒状，并弥散分布于基体上。Al3Zr／Al复合材料的界面结构研究表明，Al3Zr颗粒与Al存在一定的晶体学位向关系：[^-2^-21]Al3Zr∥[100]Al，（012）Al3Zr∥（1^-10）Al，其点阵错位度仅为10．87％，这表明Al3Zr颗粒可作为基体Al相的形核衬底。Al3Zr／Al复合材料的力学性能测试显示，当Al3Zr颗粒体积分数为11.2％时，抗拉强度和屈服强度分别为148．7MPa和110．2MPa，而且Al3Zr／Al复合材料的抗拉强度和屈服强度均随颗粒体积分数增加显著提高。
开发了Al-K2ZrF6体系熔体反应法合成原位铝基复合材料，采用XRD，SEM和TEM分析了复合材料中相组成、微观组织和界面结构。实验结果表明：合成的增强相为Al3Zr颗粒，常规金属型铸造的复合材料中其尺寸在3μm～4μm左右，一般成聚集态分布，颗粒形貌基本为长方体状：该复合材料经重熔快淬成形后，颗粒尺寸减小，基本为粒状，并弥散分布于基体上。Al3Zr／Al复合材料的界面结构研究表明，Al3Zr颗粒与Al存在一定的晶体学位向关系：[^-2^-21]Al3Zr∥[100]Al，（012）Al3Zr∥（1^-10）Al，其点阵错位度仅为10．87％，这表明Al3Zr颗粒可作为基体Al相的形核衬底。Al3Zr／Al复合材料的力学性能测试显示，当Al3Zr颗粒体积分数为11.2％时，抗拉强度和屈服强度分别为148．7MPa和110．2MPa，而且Al3Zr／Al复合材料的抗拉强度和屈服强度均随颗粒体积分数增加显著提高。
2007, 36(2):264-268.
Abstract:
In this paper,the low-cycle fatigue fracture crack growth is investigated gropingly for Zr-4 alloy(Zircaloy-4).By analyzing the trend of patulous energy and fractal dimension in the crack growth direction,three stages(A-B,D-E,and F-H) of different energies and fractal dimensions are discovered in the growth period of dynamic crack.The normalized energies are 0~0.0156,0.8754~0.9652,and 1 for the A-B,D-E,and F-H stages,respectively.But for the fractal dimension,it is in the middle for the A-B stage,its mean value and standard deviation in LL and LH directions are 2.2796,0.0277 and 2.4516,0.0592,respectively;and it is minimal for the D-E stage,its mean value and standard deviation in LL and LH directions are 2.2214,0.0131 and 2.3477,0.0550,respectively;it is maximal for the F-H stage with the mean value and standard deviation in LL and LH directions of 2.3414,0.0704 and 2.5398,0.0263,respectively.Finally,the phenomena were studied on the morphology of low-cycle fatigue fracture by SEM for Zircaloy-4.
In this paper,the low-cycle fatigue fracture crack growth is investigated gropingly for Zr-4 alloy(Zircaloy-4).By analyzing the trend of patulous energy and fractal dimension in the crack growth direction,three stages(A-B,D-E,and F-H) of different energies and fractal dimensions are discovered in the growth period of dynamic crack.The normalized energies are 0~0.0156,0.8754~0.9652,and 1 for the A-B,D-E,and F-H stages,respectively.But for the fractal dimension,it is in the middle for the A-B stage,its mean value and standard deviation in LL and LH directions are 2.2796,0.0277 and 2.4516,0.0592,respectively;and it is minimal for the D-E stage,its mean value and standard deviation in LL and LH directions are 2.2214,0.0131 and 2.3477,0.0550,respectively;it is maximal for the F-H stage with the mean value and standard deviation in LL and LH directions of 2.3414,0.0704 and 2.5398,0.0263,respectively.Finally,the phenomena were studied on the morphology of low-cycle fatigue fracture by SEM for Zircaloy-4.
2007, 36(2):269-272.
Abstract:
采用熔体快淬制备NdFe二元合金甩带，获得较细的纳米晶，经粉碎及处理后，采用体积比为50％的含量与石蜡混合，进行2GHz～12GHz频段的电磁性能测试，获得了较好的微波电磁性能，其中Nd8Fe92在2GHz处μr=4．5-j2．2，εr=128-j45，当厚度为1．2mm，分别模拟得到微波频率在4GHz附近反射率衰减为-8．5dB（86％的能量损耗），在2GHz附近衰减为-5．8dB（75％的能量损耗）的性能。模拟后可根据不同频率需要设计成在一定厚度和Nd元素含量比的微波吸收材料。
采用熔体快淬制备NdFe二元合金甩带，获得较细的纳米晶，经粉碎及处理后，采用体积比为50％的含量与石蜡混合，进行2GHz～12GHz频段的电磁性能测试，获得了较好的微波电磁性能，其中Nd8Fe92在2GHz处μr=4．5-j2．2，εr=128-j45，当厚度为1．2mm，分别模拟得到微波频率在4GHz附近反射率衰减为-8．5dB（86％的能量损耗），在2GHz附近衰减为-5．8dB（75％的能量损耗）的性能。模拟后可根据不同频率需要设计成在一定厚度和Nd元素含量比的微波吸收材料。
2007, 36(2):273-277.
Abstract:
采用草酸根沉淀稀土粒子使其充分混合进行前处理，用固相反应合成了硼钒酸钇钆铕稀土荧光红粉。对试样进行了X射线衍射、光致激发和发射光谱表征。产物与（Y，Gd）VO4：Eu相比，掺入了与钒等摩尔量的硼，硼的掺入提高了发光强度，但没有改变钒酸盐的四方晶系结构。分析了不同浓度Gd^3＋掺杂对试样发光强度的影响以及基质离子VO4^3-和BO3^3-对激活剂Eu^3＋的能量传递机理。同时将产物与（Y，Gd）VO4：Eu和（Y，Gd）BO3：Eu的发光性能进行对比，发现（Y，Gd）-（BO3，VO4）：Eu具有更好的发光强度和色纯度，有望在工业上作为一种优良的新型灯用或PDP显示器用荧光粉。所用方法与传统固相法相比，反应温度降低了100℃，所得试样易粉碎、粒度细，发光强度提高10％以上。
采用草酸根沉淀稀土粒子使其充分混合进行前处理，用固相反应合成了硼钒酸钇钆铕稀土荧光红粉。对试样进行了X射线衍射、光致激发和发射光谱表征。产物与（Y，Gd）VO4：Eu相比，掺入了与钒等摩尔量的硼，硼的掺入提高了发光强度，但没有改变钒酸盐的四方晶系结构。分析了不同浓度Gd^3＋掺杂对试样发光强度的影响以及基质离子VO4^3-和BO3^3-对激活剂Eu^3＋的能量传递机理。同时将产物与（Y，Gd）VO4：Eu和（Y，Gd）BO3：Eu的发光性能进行对比，发现（Y，Gd）-（BO3，VO4）：Eu具有更好的发光强度和色纯度，有望在工业上作为一种优良的新型灯用或PDP显示器用荧光粉。所用方法与传统固相法相比，反应温度降低了100℃，所得试样易粉碎、粒度细，发光强度提高10％以上。
2007, 36(2):278-281.
Abstract:
采用热分解法制备了钛基二氧化锡电极，并用XRD，SEM对电极涂层进行了表征，应用快速电极寿命法测试了钛基二氧化锡电极在60℃，1．0mol/L H2SO4溶液中的使用寿命。以降解苯酚为目标，用循环伏安法考察了该电极的电催化氧化性能。结果表明，苯酚转化率达到96．5％，其电催化性能优于传统单质铅电极和Ti／PbO2电极，是1种优良的电催化剂。
采用热分解法制备了钛基二氧化锡电极，并用XRD，SEM对电极涂层进行了表征，应用快速电极寿命法测试了钛基二氧化锡电极在60℃，1．0mol/L H2SO4溶液中的使用寿命。以降解苯酚为目标，用循环伏安法考察了该电极的电催化氧化性能。结果表明，苯酚转化率达到96．5％，其电催化性能优于传统单质铅电极和Ti／PbO2电极，是1种优良的电催化剂。
2007, 36(2):282-286.
Abstract:
以自制高纯乙醇钽为原料，通过水解、干燥与煅烧生产粒度约35nm的高纯Ta2O5纳米粉。研究了水解过程中乙醇钽浓度、温度、加料时间对产品粒度的影响以及煅烧温度与时间对Ta2O5晶形的影响。选取水解最佳条件为：乙醇钽浓度1.0mol／L，水解温度50℃左右，加料时间约15min。加完后，搅拌5min，接着加入氨水溶液调节pH值到8～9，同时升温至80℃-85℃保温30min；煅烧温度800℃，时间2h。得到的Ta2O5产品粒度约35nm，纯度〉99．997％。
以自制高纯乙醇钽为原料，通过水解、干燥与煅烧生产粒度约35nm的高纯Ta2O5纳米粉。研究了水解过程中乙醇钽浓度、温度、加料时间对产品粒度的影响以及煅烧温度与时间对Ta2O5晶形的影响。选取水解最佳条件为：乙醇钽浓度1.0mol／L，水解温度50℃左右，加料时间约15min。加完后，搅拌5min，接着加入氨水溶液调节pH值到8～9，同时升温至80℃-85℃保温30min；煅烧温度800℃，时间2h。得到的Ta2O5产品粒度约35nm，纯度〉99．997％。
2007, 36(2):287-290.
Abstract:
The static and dynamic mechanical properties of the 93WNiFe heavy alloy improved by adding rare earth elements of La and Ce with different contents have been studied in this paper. The results show that the mechanical properties, especially the dynamic mechanical properties, can be improved by the addition of a small amount of La and Ce for the tungsten alloy due to the reduction of the segregation of oxygen and sulfur at the interface between W grains and matrix and the reduction of the contiguity of W grains. The reasonable adding content of rare earth is 0.10%-0.15%.
The static and dynamic mechanical properties of the 93WNiFe heavy alloy improved by adding rare earth elements of La and Ce with different contents have been studied in this paper. The results show that the mechanical properties, especially the dynamic mechanical properties, can be improved by the addition of a small amount of La and Ce for the tungsten alloy due to the reduction of the segregation of oxygen and sulfur at the interface between W grains and matrix and the reduction of the contiguity of W grains. The reasonable adding content of rare earth is 0.10%-0.15%.
2007, 36(2):291-295.
Abstract:
采用Yb／Co氢氧化物共沉淀包覆方法和Ca3（PO4）2与Co（OH）2分别沉淀分层包覆方法在球形Ni（OH）2的表面进行了均匀的包覆。前者利用COSO4，YbCl3和NaOH溶液进行共沉淀包覆，后者是先在球形Ni（OH）2的表面沉淀包覆Ca3（PO4）2，然后再沉淀包覆Co（OH）2。结果显示，两种包覆方法均能有效地提高球形Ni（OH）2的高温（60℃）性能。按照Yb／Co=0．75％：2％共沉淀包覆的试样制成AA型电池后，在60℃下1C放电的容量保持率达到常温下的90％。而2％Ca3（P04）2与2％Co（OH）2分层包覆后的球形Ni（OH）2制成AA型电池后，在60℃下1C放电的容量保持率达到常温下的81％。未包覆和仅用Co（OH）2包覆的球形Ni（OH）2制成的AA型电池，在60℃下1C放电的容量保持率分别只有46％和48％。通过循环伏安测试表明，利用表面包覆的方法可以增大正极材料Ni（OH）2在高温下的氧化电位、析氧电位和两者之间的电位差，从而提高了材料在高温下的电化学性能。
采用Yb／Co氢氧化物共沉淀包覆方法和Ca3（PO4）2与Co（OH）2分别沉淀分层包覆方法在球形Ni（OH）2的表面进行了均匀的包覆。前者利用COSO4，YbCl3和NaOH溶液进行共沉淀包覆，后者是先在球形Ni（OH）2的表面沉淀包覆Ca3（PO4）2，然后再沉淀包覆Co（OH）2。结果显示，两种包覆方法均能有效地提高球形Ni（OH）2的高温（60℃）性能。按照Yb／Co=0．75％：2％共沉淀包覆的试样制成AA型电池后，在60℃下1C放电的容量保持率达到常温下的90％。而2％Ca3（P04）2与2％Co（OH）2分层包覆后的球形Ni（OH）2制成AA型电池后，在60℃下1C放电的容量保持率达到常温下的81％。未包覆和仅用Co（OH）2包覆的球形Ni（OH）2制成的AA型电池，在60℃下1C放电的容量保持率分别只有46％和48％。通过循环伏安测试表明，利用表面包覆的方法可以增大正极材料Ni（OH）2在高温下的氧化电位、析氧电位和两者之间的电位差，从而提高了材料在高温下的电化学性能。
2007, 36(2):296-300.
Abstract:
Al/Ni clad composite metal is widely applied as the external terminal of battery under the demands of both high bonding strength and low hardness of nickel layer.A better solution to the contradiction of bonding strength and controlling hardness of nickel was successfully got by adopting a controlled-atmosphere hot-bonding technology for the clad composite metal strip.The mechanism of controlled-atmosphere hot-bonding and the effects of microstructure transformation near the bonding interface on the bonding strength during annealing process were discussed in this research.The results show that:(1) the thermal activation of two metals interface can be explained by the mechanism of bonding;(2) the satisfying properties of final product can be attributed to the lower critical rolling reduction for bonding by the new technique;(3) the temperature is more important for annealing parameters to optimize the technique and to avoid the damage of intermetallic compound.
Al/Ni clad composite metal is widely applied as the external terminal of battery under the demands of both high bonding strength and low hardness of nickel layer.A better solution to the contradiction of bonding strength and controlling hardness of nickel was successfully got by adopting a controlled-atmosphere hot-bonding technology for the clad composite metal strip.The mechanism of controlled-atmosphere hot-bonding and the effects of microstructure transformation near the bonding interface on the bonding strength during annealing process were discussed in this research.The results show that:(1) the thermal activation of two metals interface can be explained by the mechanism of bonding;(2) the satisfying properties of final product can be attributed to the lower critical rolling reduction for bonding by the new technique;(3) the temperature is more important for annealing parameters to optimize the technique and to avoid the damage of intermetallic compound.
2007, 36(2):301-304.
Abstract:
利用波长1．06μm的激光对U-2Nb合金进行了表面熔化处理。结果表明；U-2Nb合金激光熔化层的显微硬度（HV）由处理前的2900MPa提高到3300MPa；合金基材为双相（α＋γ）珠光体，经激光处理后变成马氏体（α′），激光处理能细化显微组织，使Nb元素实现均匀分布。阳极极化试验与质量法腐蚀试验表明：激光处理能明显提高合金的抗腐蚀能力，在FeCl3·6H2O溶液中激光处理后合金的失重仅为处理前的1／5。
利用波长1．06μm的激光对U-2Nb合金进行了表面熔化处理。结果表明；U-2Nb合金激光熔化层的显微硬度（HV）由处理前的2900MPa提高到3300MPa；合金基材为双相（α＋γ）珠光体，经激光处理后变成马氏体（α′），激光处理能细化显微组织，使Nb元素实现均匀分布。阳极极化试验与质量法腐蚀试验表明：激光处理能明显提高合金的抗腐蚀能力，在FeCl3·6H2O溶液中激光处理后合金的失重仅为处理前的1／5。
2007, 36(2):305-308.
Abstract:
ZnS nanoparticles and one-dimensional nanocrystals were obtained by in-situ synthesis in Aa-AMPS-hT ternary periodic copolymer by ion complexometry and self-assembly method. The micro-morphology, structure and optical properties were characterized by TEM, SED, UV-vis spectra and PL spectra. The results show that the products are hexagonal ZnS nanocrystals with 15 nm-215 nm in diameter. The morphology and dimension of ZnS nanoparticles could be controlled by varying the sulfuration time. The UV-vis absorption spectra indicate that the absorption edges are blue-shifted by shortening the sulfuration time, exhibiting a marked quantum size effect. With shortening sulfuration time, the photoluminescence emission peak of 409.8 nm is blue-shifted, which could be ascribed to be the forbidden gap emission .
ZnS nanoparticles and one-dimensional nanocrystals were obtained by in-situ synthesis in Aa-AMPS-hT ternary periodic copolymer by ion complexometry and self-assembly method. The micro-morphology, structure and optical properties were characterized by TEM, SED, UV-vis spectra and PL spectra. The results show that the products are hexagonal ZnS nanocrystals with 15 nm-215 nm in diameter. The morphology and dimension of ZnS nanoparticles could be controlled by varying the sulfuration time. The UV-vis absorption spectra indicate that the absorption edges are blue-shifted by shortening the sulfuration time, exhibiting a marked quantum size effect. With shortening sulfuration time, the photoluminescence emission peak of 409.8 nm is blue-shifted, which could be ascribed to be the forbidden gap emission .
2007, 36(2):309-312.
Abstract:
An experiment was carried out on the blend of metal power 316L/binder under steady and dynamic molding conditions using the self-made electromagnetic dynamic injection machine DPII-90.The effects of vibration parameters on the uniformity and densification of metal power 316L/binder were studied.Results show that the density of green parts under dynamic molding conditions is obviously higher than under steady molding conditions.The increase of green parts's density is nonlinear under a given frequency(or amplitude) with the increase of amplitude(or frequency).The density decreases slightly as it reaches to a max value.The densification of green parts is better in the frequency range of 7 Hz~10 Hz and vibration amplitude range of 0.05 mm~0.15 mm.SEM showed that the change of uniform dispersion and distribution is basically accordant with the change of density with vibration amplitude(frequency).
An experiment was carried out on the blend of metal power 316L/binder under steady and dynamic molding conditions using the self-made electromagnetic dynamic injection machine DPII-90.The effects of vibration parameters on the uniformity and densification of metal power 316L/binder were studied.Results show that the density of green parts under dynamic molding conditions is obviously higher than under steady molding conditions.The increase of green parts's density is nonlinear under a given frequency(or amplitude) with the increase of amplitude(or frequency).The density decreases slightly as it reaches to a max value.The densification of green parts is better in the frequency range of 7 Hz~10 Hz and vibration amplitude range of 0.05 mm~0.15 mm.SEM showed that the change of uniform dispersion and distribution is basically accordant with the change of density with vibration amplitude(frequency).
2007, 36(2):313-317.
Abstract:
采用国产3Y-TZP亚微米粉体，通过双向模压结合等静压成形有效克服了条形试样的烧结弯曲，探讨了24h排胶工艺对预烧试样力学性能的影响，通过对预烧试样热膨胀曲线的测定、不同烧结温度试样力学性能和密度的比较及XRD定量分析确定了适宜的烧结工艺。结果表明，牙科支架用陶瓷，将预烧试样升至1550℃保温0．5h，排胶工艺对预烧试样的抗弯强度和断裂韧性并无显著影响，对于即可获得足够的抗弯强度，提高其断裂韧性。
采用国产3Y-TZP亚微米粉体，通过双向模压结合等静压成形有效克服了条形试样的烧结弯曲，探讨了24h排胶工艺对预烧试样力学性能的影响，通过对预烧试样热膨胀曲线的测定、不同烧结温度试样力学性能和密度的比较及XRD定量分析确定了适宜的烧结工艺。结果表明，牙科支架用陶瓷，将预烧试样升至1550℃保温0．5h，排胶工艺对预烧试样的抗弯强度和断裂韧性并无显著影响，对于即可获得足够的抗弯强度，提高其断裂韧性。
2007, 36(2):318-320.
Abstract:
Porous Palladium materials have great importance in the storage, recycle and application of hydrogen isotopes. In this paper, porous Pd materials processed by a newly applied sintering-resolving technology are studied. The microstructures of the porous Pd materials are characterized by FESEM. In addition, their hydrogen isotopes displacement and mechanic properties arc studied. The results show that porous Pd materials with a porosity range from 85.29% to 87.82% can be stably processed by sintering-resolving technology. The compressive strength of the porous Pd materials exceeds 2 MPa. The deuterium absorption amount of the porous Pd material with a porosity of 87.3% is 0.0767 L/g and its hydrogen isotopes displacement ratio is 86.2% at room temperature.
Porous Palladium materials have great importance in the storage, recycle and application of hydrogen isotopes. In this paper, porous Pd materials processed by a newly applied sintering-resolving technology are studied. The microstructures of the porous Pd materials are characterized by FESEM. In addition, their hydrogen isotopes displacement and mechanic properties arc studied. The results show that porous Pd materials with a porosity range from 85.29% to 87.82% can be stably processed by sintering-resolving technology. The compressive strength of the porous Pd materials exceeds 2 MPa. The deuterium absorption amount of the porous Pd material with a porosity of 87.3% is 0.0767 L/g and its hydrogen isotopes displacement ratio is 86.2% at room temperature.
2007, 36(2):321-324.
Abstract:
The effects of adding BaF2 on the thermodynamic behavior of YBCO precursory powders,melt-textured microstructure and properties of YBCO superconductors have been investigated.The differential thermal analysis(DTA) results showed that the peritectic decomposition and reaction temperature of YBCO precursory powder were lowered when BaF2 is added,but the temperature range for melting texture growth did not significantly change by the addition of BaF2.The microstructures of the doped samples have been observed by scanning electron microscopy(SEM).The results show that the appropriate addition amounts of BaF2 were not affect the microstructure of YBCO and the distribution of Y211 in the matrix.The transition temperature Tc was measured by susceptibility method without obviously decrease for the samples with an addition amount lower than 10wt% of BaF2.
The effects of adding BaF2 on the thermodynamic behavior of YBCO precursory powders,melt-textured microstructure and properties of YBCO superconductors have been investigated.The differential thermal analysis(DTA) results showed that the peritectic decomposition and reaction temperature of YBCO precursory powder were lowered when BaF2 is added,but the temperature range for melting texture growth did not significantly change by the addition of BaF2.The microstructures of the doped samples have been observed by scanning electron microscopy(SEM).The results show that the appropriate addition amounts of BaF2 were not affect the microstructure of YBCO and the distribution of Y211 in the matrix.The transition temperature Tc was measured by susceptibility method without obviously decrease for the samples with an addition amount lower than 10wt% of BaF2.
2007, 36(2):329-331.
Abstract:
采用HDDR工艺制备出了各向同性Sm2Fe17Nx永磁粉，通过XRD，SEM，EDX等手段研究了Sm-Fe合金的凝固，均匀化热处理，氢化-歧化以及脱氢-再化合和氮化等过程中，合金的相及微观结构的变化。结果表明：1050℃，24h的均匀化热处理能有效地消除合金中的杂相，成功地制备出成分均一的单相2：17母合金：800℃氢化-歧化1h后，合金歧化成晶粒为纳米级SmHx和α-Fe，相同温度下脱氢-再化合2h后，合金又再化合为晶粒细小的2：17相，500℃氮化5h后，合金大量吸氮，晶格常数和单胞体积明显增加，体积膨胀量达6．28％；将上述制备的各向同性Sm2Fe17Nx永磁粉用质量分数为3％的环氧树脂粘结剂均匀包缚，获得了密度为6．04g／cm^3，磁性能为：Br=0．6704T，Hcj=015kA／m，（BH）max=73．7kJ/m^3的各向同性Sm2Fe17M粘结磁体。
采用HDDR工艺制备出了各向同性Sm2Fe17Nx永磁粉，通过XRD，SEM，EDX等手段研究了Sm-Fe合金的凝固，均匀化热处理，氢化-歧化以及脱氢-再化合和氮化等过程中，合金的相及微观结构的变化。结果表明：1050℃，24h的均匀化热处理能有效地消除合金中的杂相，成功地制备出成分均一的单相2：17母合金：800℃氢化-歧化1h后，合金歧化成晶粒为纳米级SmHx和α-Fe，相同温度下脱氢-再化合2h后，合金又再化合为晶粒细小的2：17相，500℃氮化5h后，合金大量吸氮，晶格常数和单胞体积明显增加，体积膨胀量达6．28％；将上述制备的各向同性Sm2Fe17Nx永磁粉用质量分数为3％的环氧树脂粘结剂均匀包缚，获得了密度为6．04g／cm^3，磁性能为：Br=0．6704T，Hcj=015kA／m，（BH）max=73．7kJ/m^3的各向同性Sm2Fe17M粘结磁体。
Liu Jide
,
Jin Tao
,
Zhao Nairen
,
Wang Zhihui
,
Liu Jinlai
,
Sun Xiaofeng
,
Guan Hengrong
,
Hu Zhuangqi
2007, 36(2):332-334.
Abstract:
采用Ni-Cr-B非晶中间层瞬间液相连接（Transient liquid phase bonding） 一种镍基单晶高温合金DD98，TLP连接在1230℃，8h真空条件下进行。利用扫描电镜进行微观组织观察和成分分析。在不同温度对接头与母材进行了拉伸实验。实验结果表明：接头的微观组织和化学成分与母材趋于一致；接头强度达到母材的标准，其它性能指标与母材相当，二者的应力一应变关系相同。
采用Ni-Cr-B非晶中间层瞬间液相连接（Transient liquid phase bonding） 一种镍基单晶高温合金DD98，TLP连接在1230℃，8h真空条件下进行。利用扫描电镜进行微观组织观察和成分分析。在不同温度对接头与母材进行了拉伸实验。实验结果表明：接头的微观组织和化学成分与母材趋于一致；接头强度达到母材的标准，其它性能指标与母材相当，二者的应力一应变关系相同。
2007, 36(2):335-338.
Abstract:
采用高能球磨方法制备了PM304复合粉末。研究了纳米PM304粉末的真空烧结致密化和显微组织演化现象，并与未球磨粉末的烧结试样进行了比较。结果表明，提高烧结温度和延长烧结时间有利于提高相对密度，同时组织长大。1100℃，2h是最佳烧结工艺。机械合金化导致粉末纳米化，使真空烧结后的显微组织结构明显细化，使试样的相对密度和抗拉强度比未球磨粉末烧结后的试样有显著提高。
采用高能球磨方法制备了PM304复合粉末。研究了纳米PM304粉末的真空烧结致密化和显微组织演化现象，并与未球磨粉末的烧结试样进行了比较。结果表明，提高烧结温度和延长烧结时间有利于提高相对密度，同时组织长大。1100℃，2h是最佳烧结工艺。机械合金化导致粉末纳米化，使真空烧结后的显微组织结构明显细化，使试样的相对密度和抗拉强度比未球磨粉末烧结后的试样有显著提高。
Xiong Li
,
Li Meicheng
,
Qiu Yongxin
,
Zhang Baoshun
,
Li Lin
,
Liu Guojun
,
Zhao Liancheng
,
Weihai
,
China;. Harbin Institute of Technology
,
Harbin
,
China;.Changchun University of Science
,
Technology
,
Changchun
,
China)
2007, 36(2):339-343.
Abstract:
研究了用分子束外延（MBE）在GaAs衬底上生长GaSb薄膜的工艺。为了减小因晶格失配度较大所引起的位错密度，采用低温GaSb作为缓冲层，有效降低了外延层中的位错密度，提高了晶体质量。通过X射线双晶衍射仪和原子力显微镜测试分析，得到低温GaSb缓冲层的优化生长参数：厚度为20nm，生长速率为1．43μm／h，Ⅴ／Ⅲ束流比为2．0。并在此基础上研究了GaSb薄膜的发光特性：GaSb薄膜的光致发光光谱主要由束缚激子（BE4）和施主-受主对（D-A）辐射复合发光峰组成，在50K时其发光峰强度最强，半峰宽最窄。
研究了用分子束外延（MBE）在GaAs衬底上生长GaSb薄膜的工艺。为了减小因晶格失配度较大所引起的位错密度，采用低温GaSb作为缓冲层，有效降低了外延层中的位错密度，提高了晶体质量。通过X射线双晶衍射仪和原子力显微镜测试分析，得到低温GaSb缓冲层的优化生长参数：厚度为20nm，生长速率为1．43μm／h，Ⅴ／Ⅲ束流比为2．0。并在此基础上研究了GaSb薄膜的发光特性：GaSb薄膜的光致发光光谱主要由束缚激子（BE4）和施主-受主对（D-A）辐射复合发光峰组成，在50K时其发光峰强度最强，半峰宽最窄。
2007, 36(2):344-348.
Abstract:
采用热分解法制备了一种以离子镀TiN膜为基体的IrO2＋Ta2O5涂层电极，通过极化曲线、循环伏安、电化学阻抗谱等电化学方法并结合扫描电镜、X射线能谱和X射线衍射研究了涂层的析氧电催化活性，并对460℃制备的涂层进行强化寿命实验。结果表明：涂层呈多孔、多裂纹的显微结构和多层电化学结构；制备温度对涂层表面形貌和电催化活性影响很大；该涂层阳极在保持了高电催化活性的同时，其使用寿命高于传统Ti基阳极，说明TiN作为此类催化电极的载体是可行的。
采用热分解法制备了一种以离子镀TiN膜为基体的IrO2＋Ta2O5涂层电极，通过极化曲线、循环伏安、电化学阻抗谱等电化学方法并结合扫描电镜、X射线能谱和X射线衍射研究了涂层的析氧电催化活性，并对460℃制备的涂层进行强化寿命实验。结果表明：涂层呈多孔、多裂纹的显微结构和多层电化学结构；制备温度对涂层表面形貌和电催化活性影响很大；该涂层阳极在保持了高电催化活性的同时，其使用寿命高于传统Ti基阳极，说明TiN作为此类催化电极的载体是可行的。
2007, 36(2):359-362.
Abstract:
采用固相法和水热法制备了BaAl2B2O7：Eu^3＋系列发光体，研究了制备方法对其光谱特性的影响、助熔剂对发光强度和微观形貌的影响、激活剂浓度对发射强度的影响。研究表明；固相法制备的发光体Eu^3＋存在621nm的^5D0→^7F2强发射和772nm的^5Do→^7F5．6弱发射，通过对多种助熔剂优选NaF为最佳的助熔剂，掺杂NaF的发光体仅在772nm的发射大幅度增强，说明助熔剂对发射光谱的特定波长有突出的增强作用：当掺杂Eu^3＋浓度较低时和水热法制备的荧光体在455nm存在Eu^2＋的4f^65d^1→^8S7／2强发射；此外还研究了BaAl2B2O7：Eu^3＋中Eu^2＋→Eu^3＋的能量传递。
采用固相法和水热法制备了BaAl2B2O7：Eu^3＋系列发光体，研究了制备方法对其光谱特性的影响、助熔剂对发光强度和微观形貌的影响、激活剂浓度对发射强度的影响。研究表明；固相法制备的发光体Eu^3＋存在621nm的^5D0→^7F2强发射和772nm的^5Do→^7F5．6弱发射，通过对多种助熔剂优选NaF为最佳的助熔剂，掺杂NaF的发光体仅在772nm的发射大幅度增强，说明助熔剂对发射光谱的特定波长有突出的增强作用：当掺杂Eu^3＋浓度较低时和水热法制备的荧光体在455nm存在Eu^2＋的4f^65d^1→^8S7／2强发射；此外还研究了BaAl2B2O7：Eu^3＋中Eu^2＋→Eu^3＋的能量传递。
2007, 36(2):363-366.
Abstract:
分别在不同进料比、进料位置、加热／冷却温度的条件下，对TCAP工艺的全回流模式进行了实验。结果表明：从回流柱进料90％，分离柱加热／冷却温度为290℃／56℃条件下的分离效果最好，40次循环后分离系数为2183.87，60次循环后分离系数达到了3055．49，40次循环后产品端D含量高于99％，尾气端H含量高于95％；分离柱中点进料的分离效果远远没有回流柱进料的好。另外，高低温差、回流比对氢同位素分离也有影响，温差越大，加热温度越高，Pd／K解吸出的H含量越高，回流比越大，TCAP分离效果就越好。
分别在不同进料比、进料位置、加热／冷却温度的条件下，对TCAP工艺的全回流模式进行了实验。结果表明：从回流柱进料90％，分离柱加热／冷却温度为290℃／56℃条件下的分离效果最好，40次循环后分离系数为2183.87，60次循环后分离系数达到了3055．49，40次循环后产品端D含量高于99％，尾气端H含量高于95％；分离柱中点进料的分离效果远远没有回流柱进料的好。另外，高低温差、回流比对氢同位素分离也有影响，温差越大，加热温度越高，Pd／K解吸出的H含量越高，回流比越大，TCAP分离效果就越好。
2007, 36(2):367-371.
Abstract:
The preparation technology and development on the single crystals of refractory metals of their alloys were introduced in this paper.Some suggestions have been given on the R&D prospects of processing technology for the single crystals of refractory alloys to enhance the high temperature creep resistance.
The preparation technology and development on the single crystals of refractory metals of their alloys were introduced in this paper.Some suggestions have been given on the R&D prospects of processing technology for the single crystals of refractory alloys to enhance the high temperature creep resistance.
2007, 36(2):372-376.
Abstract:
These is a lot of platinum precious metals(FPs) in the spent nuclear waste,such as Ru,Rh,and Pd.This FPs were generated through nuclear fission reaction in nuclear power reactor.Now in the worldwide,the quantity of FPs in the spent nuclear waste is no less than quantity of precious metals resource in the nature.This number of FPs will continue to increase.In the future,the FPs will be the important resource for precious metals.In this paper,methods of extraction and sate of FPs in the nuclear waste were introduced.The radioactive properties of every species of FPs were all listed.Viewpoints and methods about how to apply and develop the FPs were given in this paper.The applications of FPs in nuclear technology and high purity hydrogen gas production were intruduced,and other potential utilizations of FPs were presented.
These is a lot of platinum precious metals(FPs) in the spent nuclear waste,such as Ru,Rh,and Pd.This FPs were generated through nuclear fission reaction in nuclear power reactor.Now in the worldwide,the quantity of FPs in the spent nuclear waste is no less than quantity of precious metals resource in the nature.This number of FPs will continue to increase.In the future,the FPs will be the important resource for precious metals.In this paper,methods of extraction and sate of FPs in the nuclear waste were introduced.The radioactive properties of every species of FPs were all listed.Viewpoints and methods about how to apply and develop the FPs were given in this paper.The applications of FPs in nuclear technology and high purity hydrogen gas production were intruduced,and other potential utilizations of FPs were presented.
