Volume 35,Issue 9,2006 Table of Contents
2006, 35(9):1345-1349.
Abstract:
China is rich in rare earth and alkaline earth elements. This paper introduced the applications of rare earth and alkaline earth elements to the heat resistant magnesium alloys, such as Mg-Al based alloys for automotive power-train system, especially summarized the effects of rare earth and alkaline earth elements on the heat resistance of Mg-Al based alloys. It is concluded that to development the rare earth and alkaline earth magnesium alloys with high performances is one of the important orientations for the future automotive industry.
China is rich in rare earth and alkaline earth elements. This paper introduced the applications of rare earth and alkaline earth elements to the heat resistant magnesium alloys, such as Mg-Al based alloys for automotive power-train system, especially summarized the effects of rare earth and alkaline earth elements on the heat resistance of Mg-Al based alloys. It is concluded that to development the rare earth and alkaline earth magnesium alloys with high performances is one of the important orientations for the future automotive industry.
2006, 35(9):1350-1353.
Abstract:
The importance of developing positive materials of lithium manganese oxide for lithium ion battery is expounded, and the applications of 3d transition metal ions (Cr3+, Ni2+, Cu2+, Fe3+) doped in positive materials of lithium manganese oxide are introduced. Effects of 3d transition metal ion doped on structure and electrochemical performance of positive materials of lithium manganese oxide are studied, and the mechanism of influences on the cycle and charge-discharge performance of lithium ion battery is proposed. The development foreground of 3d transition metal ions doped in positive materials of lithium manganese oxide is viewed. It is suggested that the LiNi0.5Mn1.5O4 has the promising application foreground for positive materials of 5 V lithium ion battery.
The importance of developing positive materials of lithium manganese oxide for lithium ion battery is expounded, and the applications of 3d transition metal ions (Cr3+, Ni2+, Cu2+, Fe3+) doped in positive materials of lithium manganese oxide are introduced. Effects of 3d transition metal ion doped on structure and electrochemical performance of positive materials of lithium manganese oxide are studied, and the mechanism of influences on the cycle and charge-discharge performance of lithium ion battery is proposed. The development foreground of 3d transition metal ions doped in positive materials of lithium manganese oxide is viewed. It is suggested that the LiNi0.5Mn1.5O4 has the promising application foreground for positive materials of 5 V lithium ion battery.
2006, 35(9):1354-1358.
Abstract:
The isothermal compression of TA 15 alloy has been carried out at a Thermecmaster-Z simulator. The experimental results show that the peak stress and steady stress decrease greatly with increasing of deformation temperature and decreasing of strain rate, and that the deformation temperature will affect the threshold strain to transmit the steady deformation. According to the experimental results, the obtained processing map presents two unsteady zones of high temperature deformation of TA 15 alloy, including the zone above 1300 K of deformation temperature and 10.0 s^-1 of strain rate and another zone below 1200 K of deformation temperature and 0.006 s^-1- 1.995 s^-1 of strain rates. Meanwhile, the present constitutive equation represents the effect of deformation temperature, strain rate and strain on flow stress in high temperature deformation of TA15 alloy. The calculated results of flow stress are in good agreement with the experimental results in high temperature deformation of TA 15 alloy.
The isothermal compression of TA 15 alloy has been carried out at a Thermecmaster-Z simulator. The experimental results show that the peak stress and steady stress decrease greatly with increasing of deformation temperature and decreasing of strain rate, and that the deformation temperature will affect the threshold strain to transmit the steady deformation. According to the experimental results, the obtained processing map presents two unsteady zones of high temperature deformation of TA 15 alloy, including the zone above 1300 K of deformation temperature and 10.0 s^-1 of strain rate and another zone below 1200 K of deformation temperature and 0.006 s^-1- 1.995 s^-1 of strain rates. Meanwhile, the present constitutive equation represents the effect of deformation temperature, strain rate and strain on flow stress in high temperature deformation of TA15 alloy. The calculated results of flow stress are in good agreement with the experimental results in high temperature deformation of TA 15 alloy.
2006, 35(9):1363-1366.
Abstract:
Laser cladding experiment of Ti+TiC was carried out on Ti-6Al-4V alloy surface.The microstructure of the clad layer was observed by SEM.The microstructure and its formation mechanism have been explained by using a microstructure formation process model.The titanium based composite made from Ti+TiC powders by laser cladding has been analyzed from the aspects of preparation process,quality,technology,production cost and reinforcing effect.
Laser cladding experiment of Ti+TiC was carried out on Ti-6Al-4V alloy surface.The microstructure of the clad layer was observed by SEM.The microstructure and its formation mechanism have been explained by using a microstructure formation process model.The titanium based composite made from Ti+TiC powders by laser cladding has been analyzed from the aspects of preparation process,quality,technology,production cost and reinforcing effect.
Zhang Chaowu
,
Zhou Lian
,
Tang Xiande
,
Jean-Louis Soubeyroux
,
Andre Sulpice
,
Zhang Pingxiang
,
Lu Yafeng
2006, 35(9):1367-1370.
Abstract:
Two kinds of ITER internal-Sn Nb3Sn superconducting wires were chosen to investigate the effects of Sn core or Nb core alloyed with the third element on A15 phase formation and superconducting performances in this paper.In-situ neutron diffraction was used for measurement of phase formation progress during the heat treatment procedure.From the obtained results it can be concluded that Sn core alloyed with small amount of the third element Ti is more effective than Nb core alloyed with Ta in enhancing A15 phase formation and improving superconducting performances.The reason may be as follows:small amount of Ti addition will not only greatly increase the tin diffusion rate and A15 phase formation rate,but also effectively inhibit the Nb3Sn grain growth and elevate the pinning force,resulting in obvious improving of superconducting performances and the large increment of non-Cu critical current density Jcn.
Two kinds of ITER internal-Sn Nb3Sn superconducting wires were chosen to investigate the effects of Sn core or Nb core alloyed with the third element on A15 phase formation and superconducting performances in this paper.In-situ neutron diffraction was used for measurement of phase formation progress during the heat treatment procedure.From the obtained results it can be concluded that Sn core alloyed with small amount of the third element Ti is more effective than Nb core alloyed with Ta in enhancing A15 phase formation and improving superconducting performances.The reason may be as follows:small amount of Ti addition will not only greatly increase the tin diffusion rate and A15 phase formation rate,but also effectively inhibit the Nb3Sn grain growth and elevate the pinning force,resulting in obvious improving of superconducting performances and the large increment of non-Cu critical current density Jcn.
2006, 35(9):1371-1374.
Abstract:
研究了（Ti0.1V0.9）100-xFex（x=0～6）合金的微观结构及其吸放氢特性。微结构分析表明，合金均由单一的体心立方（bcc）结构的钒基固溶体相组成；合金的点阵常数随着Fe含量的增加呈线性递减，晶胞体积也随之逐渐降低。储氢性能测试表明，所有合金的动力学性能均比较好，在10℃和4MPa初始氢压条件下，合金无需氢化孕育期就能吸氢。随着Fe含量从x=0增加至x=6，合金的活化性能得到改善；10℃最大吸氢量从509．5ml／g逐渐降至424．8ml／g；50℃有效放氢量先升后降，并在x=4时达到最高值255．6ml／g。在所研究的合金中，Ti9.6V86.4Fe4合金具有最佳综合性能，经2次吸放氢循环即可活化，10℃最大吸氢量为494．5ml／g，50℃有效放氢量达到255．6ml／g。
研究了（Ti0.1V0.9）100-xFex（x=0～6）合金的微观结构及其吸放氢特性。微结构分析表明，合金均由单一的体心立方（bcc）结构的钒基固溶体相组成；合金的点阵常数随着Fe含量的增加呈线性递减，晶胞体积也随之逐渐降低。储氢性能测试表明，所有合金的动力学性能均比较好，在10℃和4MPa初始氢压条件下，合金无需氢化孕育期就能吸氢。随着Fe含量从x=0增加至x=6，合金的活化性能得到改善；10℃最大吸氢量从509．5ml／g逐渐降至424．8ml／g；50℃有效放氢量先升后降，并在x=4时达到最高值255．6ml／g。在所研究的合金中，Ti9.6V86.4Fe4合金具有最佳综合性能，经2次吸放氢循环即可活化，10℃最大吸氢量为494．5ml／g，50℃有效放氢量达到255．6ml／g。
2006, 35(9):1375-1378.
Abstract:
The cyclic properties of hydrogen absorption and desorption in V55Ti20.5Cr18.1Fe6.4 alloy were studied. With increasing of cyclic number, the hydrogen content drops and the decay rate of hydrogen desorption content slows down. The hydrogen desorption plateau region becomes narrowed and the hydrogen desorption pressure increases with increasing of cyclic number. Some compounds deteriorating the alloy property appear on the alloy surface and the alloy shows double phase structure with of bcc and fee after cycles. The alloy grains have been pulverized gradually due to the accumulation of cracks introduced during the absorption-desorption cycles.
The cyclic properties of hydrogen absorption and desorption in V55Ti20.5Cr18.1Fe6.4 alloy were studied. With increasing of cyclic number, the hydrogen content drops and the decay rate of hydrogen desorption content slows down. The hydrogen desorption plateau region becomes narrowed and the hydrogen desorption pressure increases with increasing of cyclic number. Some compounds deteriorating the alloy property appear on the alloy surface and the alloy shows double phase structure with of bcc and fee after cycles. The alloy grains have been pulverized gradually due to the accumulation of cracks introduced during the absorption-desorption cycles.
2006, 35(9):1383-1387.
Abstract:
The geometrical and electronic structures for LaNi4.75Al0.25 compound have been calculated with the generalized gradient approximation(GGA)Pewdew96 of density functional and the Full-potential linearized augmented plane wave(FLAPW)method.The results indicate that the optimized cell parameters are a=b=0.5033 nm,c=0.4018 nm and a/c=1.252,and Al atom is most likely to occupy the(0.75,0.0,0.5)position in the super-cell-the equivalent position of 3g of LaNi5 mono-cell.The band structure,density of states(DOS)and charge densities for this compound are also worked out.All the theoretical results are in well agreement with the experimental data.
The geometrical and electronic structures for LaNi4.75Al0.25 compound have been calculated with the generalized gradient approximation(GGA)Pewdew96 of density functional and the Full-potential linearized augmented plane wave(FLAPW)method.The results indicate that the optimized cell parameters are a=b=0.5033 nm,c=0.4018 nm and a/c=1.252,and Al atom is most likely to occupy the(0.75,0.0,0.5)position in the super-cell-the equivalent position of 3g of LaNi5 mono-cell.The band structure,density of states(DOS)and charge densities for this compound are also worked out.All the theoretical results are in well agreement with the experimental data.
2006, 35(9):1392-1395.
Abstract:
Adopting process of tagnite, effects of three current controlling, modes, namely constant current, unipolar current and bipolar current on properties of anodic coatings of AZ91HP magnesium alloys were studied, coatings formed by the three methods were all compact, the number of pores per unit by bipolar current was the least among them , and there was no difference between those by constant current and unipolar current. The uniformity of pore size for the coating obtained by bipolar current was the best and that by constant current was the worst. According to EDS analysis, these coatings contained Si, O, Mg and F. Salt spray test showed that corrosion resistance of the coating by bipolar current was the best and the coating by constant current the worst.
Adopting process of tagnite, effects of three current controlling, modes, namely constant current, unipolar current and bipolar current on properties of anodic coatings of AZ91HP magnesium alloys were studied, coatings formed by the three methods were all compact, the number of pores per unit by bipolar current was the least among them , and there was no difference between those by constant current and unipolar current. The uniformity of pore size for the coating obtained by bipolar current was the best and that by constant current was the worst. According to EDS analysis, these coatings contained Si, O, Mg and F. Salt spray test showed that corrosion resistance of the coating by bipolar current was the best and the coating by constant current the worst.
2006, 35(9):1396-1399.
Abstract:
研究了以HFC-134a气体为基的混合气体的保护效果，形成的保护膜形貌，结构及成分：分析了各种元素在保护膜中所起的作用。实验研究表明：保护膜由MgO和MgF2混合生成，厚度一般在0．1μm～0．6μm，且保护膜在厚度方向上成分均匀；在保护膜和基体之间存在大量MgF2的聚集颗粒，这些颗粒在表面呈凹陷状。
研究了以HFC-134a气体为基的混合气体的保护效果，形成的保护膜形貌，结构及成分：分析了各种元素在保护膜中所起的作用。实验研究表明：保护膜由MgO和MgF2混合生成，厚度一般在0．1μm～0．6μm，且保护膜在厚度方向上成分均匀；在保护膜和基体之间存在大量MgF2的聚集颗粒，这些颗粒在表面呈凹陷状。
2006, 35(9):1400-1403.
Abstract:
向AZ91镁合金中加入具有阻燃作用的合金元素Ca和Y，研究了单独加入Ca和同时加入Ca，Y对AZ91合金铸态显微组织和力学性能的影响。结果表明：向AZ91合金中单独加入Ca可使该合金的铸态组织明显细化，当Ca含量大于1ω％时，合金铸态组织中生成了Al2Ca新相，使该合金的抗拉强度得到提高。在此基础上加入少量的Y（0．10％-0．50％）（质量分数，下同）可使合金的铸态组织进一步细化，该合金的抗拉强度随Y含最的增加先提高后降低。
向AZ91镁合金中加入具有阻燃作用的合金元素Ca和Y，研究了单独加入Ca和同时加入Ca，Y对AZ91合金铸态显微组织和力学性能的影响。结果表明：向AZ91合金中单独加入Ca可使该合金的铸态组织明显细化，当Ca含量大于1ω％时，合金铸态组织中生成了Al2Ca新相，使该合金的抗拉强度得到提高。在此基础上加入少量的Y（0．10％-0．50％）（质量分数，下同）可使合金的铸态组织进一步细化，该合金的抗拉强度随Y含最的增加先提高后降低。
2006, 35(9):1404-1407.
Abstract:
A large volumetric fraction of icosahedral quasicrystal was gained through ordinary solidification technology in Mg-Zn-Y ternary alloys.The icosahedral quasicrystal in Mg-Zn-Y ternary alloys have two typical morphology features:petal-like,polygon-like.The different features of icosahedral quasicrystal are attributed to their morphology evolution.Alloying composition and cooling rate are major factors affecting the morphology of icosahedral quasicrystal.In the solidification process of quasicrystal alloys,the more the low-temperature phases and the less the cooling rate,the much more easily the changing into the polygon-like morphology from petal-like one takes place.Peritectic reaction occurs during the icosahedral quasicrystal formation which leads to element content difference in primary stage and in final stage of icosahedral quasicrystal evolution.The composition analyses show that Mg content is lower but Zn and Y contents are higher in the primary stage of quasicrystal growth.
A large volumetric fraction of icosahedral quasicrystal was gained through ordinary solidification technology in Mg-Zn-Y ternary alloys.The icosahedral quasicrystal in Mg-Zn-Y ternary alloys have two typical morphology features:petal-like,polygon-like.The different features of icosahedral quasicrystal are attributed to their morphology evolution.Alloying composition and cooling rate are major factors affecting the morphology of icosahedral quasicrystal.In the solidification process of quasicrystal alloys,the more the low-temperature phases and the less the cooling rate,the much more easily the changing into the polygon-like morphology from petal-like one takes place.Peritectic reaction occurs during the icosahedral quasicrystal formation which leads to element content difference in primary stage and in final stage of icosahedral quasicrystal evolution.The composition analyses show that Mg content is lower but Zn and Y contents are higher in the primary stage of quasicrystal growth.
2006, 35(9):1408-1411.
Abstract:
利用扫描电镜和能谱分析研究了产生黑斑的GH3044组织,采用Thermal-Calc分析方法研究了合金凝固过程中液体成分变化,并计算了合金凝固时液体密度的变化,给出了GH3044合金平衡凝固时密度反转的范围。结果表明:合金GH3044黑斑区主要是由Cr,W的碳化物相和少量高W(Cr)的体心立方相组成,合金在凝固过程中约有0.0125g·cm-3·℃-1较大的密度反转。
利用扫描电镜和能谱分析研究了产生黑斑的GH3044组织,采用Thermal-Calc分析方法研究了合金凝固过程中液体成分变化,并计算了合金凝固时液体密度的变化,给出了GH3044合金平衡凝固时密度反转的范围。结果表明:合金GH3044黑斑区主要是由Cr,W的碳化物相和少量高W(Cr)的体心立方相组成,合金在凝固过程中约有0.0125g·cm-3·℃-1较大的密度反转。
2006, 35(9):1412-1417.
Abstract:
研究了Waspaloy高温合金在扩大锭型后，铸锭中元素偏析程度和均匀化处理过程中元素偏析规律并建立理论模型。采用光学显微镜、扫描电镜、能谱仪分析了该合金铸态和均匀化态的显微组织和元素的偏析规律，以此为基础分析并建立了偏析指数与材料工艺参数的关系，为扩大锭型后均匀化制度的合理制订提供理论依据。同时认为φ508mm铸锭的均匀化应分为2个阶段进行，第1阶段为1120℃的低熔点组织溶解，第2阶段为1180℃左右进行Ti，Cr元素的扩散，改善偏析。结果表明：合金在1180℃退火20h较合理。
研究了Waspaloy高温合金在扩大锭型后，铸锭中元素偏析程度和均匀化处理过程中元素偏析规律并建立理论模型。采用光学显微镜、扫描电镜、能谱仪分析了该合金铸态和均匀化态的显微组织和元素的偏析规律，以此为基础分析并建立了偏析指数与材料工艺参数的关系，为扩大锭型后均匀化制度的合理制订提供理论依据。同时认为φ508mm铸锭的均匀化应分为2个阶段进行，第1阶段为1120℃的低熔点组织溶解，第2阶段为1180℃左右进行Ti，Cr元素的扩散，改善偏析。结果表明：合金在1180℃退火20h较合理。
2006, 35(9):1418-1423.
Abstract:
Bioactive calcium phosphate coating was prepared on C/C composites by sonoelectrodeposition technique. The analyses by SEM, XRD, FRIR and EDS show that as-received coating exhibiting subtle net-like morphology is composed of carbonate hydroxyapatite with the Ca/P ratio of 1.64. On the base of SEM observation, the procedure of the formation of apatite on C/C composite is described. We suggest that the procedure of HA deposition could be simplified to two steps, e.g. the movement of ions including Ca and P species toward C/C cathode and the growth of HA on the surface of C/C composite. In virtue of this description, the kinetics formulas of HA deposition is derived and it is found that the deposition procedure is controlled by ion diffusion in the electrolyte and the diffusion activation energy is 30.3 kJ/mol.
Bioactive calcium phosphate coating was prepared on C/C composites by sonoelectrodeposition technique. The analyses by SEM, XRD, FRIR and EDS show that as-received coating exhibiting subtle net-like morphology is composed of carbonate hydroxyapatite with the Ca/P ratio of 1.64. On the base of SEM observation, the procedure of the formation of apatite on C/C composite is described. We suggest that the procedure of HA deposition could be simplified to two steps, e.g. the movement of ions including Ca and P species toward C/C cathode and the growth of HA on the surface of C/C composite. In virtue of this description, the kinetics formulas of HA deposition is derived and it is found that the deposition procedure is controlled by ion diffusion in the electrolyte and the diffusion activation energy is 30.3 kJ/mol.
2006, 35(9):1424-1427.
Abstract:
Inconel alloy 690 and Inconel alloy 693 were chosen as the electrode materials in this study and their corrosion behaviors in iron phosphate glass melt containing low activity(LAW)nuclear waste was explored.The corrosion losses in size and weight of different materials in glass melt were calculated.The corrosion layer formed on the surface of the alloys was analyzed by Scanning Electron Microscope(SEM),Energy Dispersive X-Ray analysis(EDS)and X-ray diffraction(XRD),and the corrosion mechanism was discussed.Results show that the Inconel alloy 693 is more stable than the Inconel alloy 690 in the glass melt.A kind of solid solution,(Fe,Cr)2O3,was believed to be the main crystalline phase in the corrosion layer on the surface of alloy samples.
Inconel alloy 690 and Inconel alloy 693 were chosen as the electrode materials in this study and their corrosion behaviors in iron phosphate glass melt containing low activity(LAW)nuclear waste was explored.The corrosion losses in size and weight of different materials in glass melt were calculated.The corrosion layer formed on the surface of the alloys was analyzed by Scanning Electron Microscope(SEM),Energy Dispersive X-Ray analysis(EDS)and X-ray diffraction(XRD),and the corrosion mechanism was discussed.Results show that the Inconel alloy 693 is more stable than the Inconel alloy 690 in the glass melt.A kind of solid solution,(Fe,Cr)2O3,was believed to be the main crystalline phase in the corrosion layer on the surface of alloy samples.
2006, 35(9):1428-1431.
Abstract:
In this paper the influence of CuSO4, HCHO and NaOH concentrations on the alkaline chemical plating of Ca is discussed and an applicable plating solution for the fabrication of copper interconnect tfor ULSI is then derived. The application of acid-alkaline combined chemical plating of Ca to ULSI interconnect is studied. At first the acid chemical plating of Cu is employed to fabricate the copper seed layer on TiN barrier, and then the alkaline chemical plating of Cu is followed to achieve Cu films. Through the study, we find that the morphology and crystallography orthe seed layer has an important effect on the as-deposited Cu films.
In this paper the influence of CuSO4, HCHO and NaOH concentrations on the alkaline chemical plating of Ca is discussed and an applicable plating solution for the fabrication of copper interconnect tfor ULSI is then derived. The application of acid-alkaline combined chemical plating of Ca to ULSI interconnect is studied. At first the acid chemical plating of Cu is employed to fabricate the copper seed layer on TiN barrier, and then the alkaline chemical plating of Cu is followed to achieve Cu films. Through the study, we find that the morphology and crystallography orthe seed layer has an important effect on the as-deposited Cu films.
2006, 35(9):1432-1436.
Abstract:
利用溶胶-凝胶法与加温、加压-流延工艺成功地制备出锐钛矿与金红石2种TiO2的质子交换复合膜。通过XRD，FTIR，EDS和AFM方法研究了复合膜晶形信息、化合键信息、元素分布、表面粗糙度，并组装了燃料电池进行了电化学测试。实验表明：TiO2掺杂全氟磺酸树脂的复合膜能在干气的操作条件下自增湿发电，电化学稳定，最高功率密度超过1W／cm^2；而且发现在复合膜中掺杂物的晶形影响燃料电池的自增湿发电性能，在70℃，0．2MPa，化学计量数为1．5的干H2／干O2操作环境下，锐钛矿型复合膜在0．55V下的电流密度接近2A／cm^2，比金红石犁复合膜增大了0.34A／cm^2，表现出了优良的自增湿电化学性能。最后讨论了TiO2／PFSA复合膜的质子传递机理。
利用溶胶-凝胶法与加温、加压-流延工艺成功地制备出锐钛矿与金红石2种TiO2的质子交换复合膜。通过XRD，FTIR，EDS和AFM方法研究了复合膜晶形信息、化合键信息、元素分布、表面粗糙度，并组装了燃料电池进行了电化学测试。实验表明：TiO2掺杂全氟磺酸树脂的复合膜能在干气的操作条件下自增湿发电，电化学稳定，最高功率密度超过1W／cm^2；而且发现在复合膜中掺杂物的晶形影响燃料电池的自增湿发电性能，在70℃，0．2MPa，化学计量数为1．5的干H2／干O2操作环境下，锐钛矿型复合膜在0．55V下的电流密度接近2A／cm^2，比金红石犁复合膜增大了0.34A／cm^2，表现出了优良的自增湿电化学性能。最后讨论了TiO2／PFSA复合膜的质子传递机理。
2006, 35(9):1437-1440.
Abstract:
不同偏压下利用多弧离子镀技术在U基体上制备了TiN薄膜。利用X射线衍射（XRD）分析了薄膜的微观组织结构，用扫描电镜（SEM）观察其表面形貌。结果表明：所得薄膜为单一TiN结构，薄膜表面平整、致密，但局部仍存在大颗粒。摩擦磨损实验测定了薄膜的磨损性能。随偏压的上升，摩擦系数由0．421变为0．401。同时利用X射线光电子能谱分析仪（XPS）对湿热腐蚀20d后的样品进行了分析，并利用电化学极化实验在0．5μg/g CT溶液中测试了基体及薄膜耐蚀性能。结果表明：TiN涂层提高了贫铀的抗腐蚀性能。
不同偏压下利用多弧离子镀技术在U基体上制备了TiN薄膜。利用X射线衍射（XRD）分析了薄膜的微观组织结构，用扫描电镜（SEM）观察其表面形貌。结果表明：所得薄膜为单一TiN结构，薄膜表面平整、致密，但局部仍存在大颗粒。摩擦磨损实验测定了薄膜的磨损性能。随偏压的上升，摩擦系数由0．421变为0．401。同时利用X射线光电子能谱分析仪（XPS）对湿热腐蚀20d后的样品进行了分析，并利用电化学极化实验在0．5μg/g CT溶液中测试了基体及薄膜耐蚀性能。结果表明：TiN涂层提高了贫铀的抗腐蚀性能。
2006, 35(9):1441-1444.
Abstract:
利用DSC，DTA，XRD研究了NiTiZrAlCuSi块体非晶合金的形成。采用铜模铸造工艺使块体金属玻璃最大直径从Ni42Ti25Zr25Al8合金的小于0．5mm增加到Ni42Ti20Zr25Al8Cu5的1mm，然后增加到Ni42Ti20Zr21.5Al8Cu5Si3.5合金的4mm。在Ni42Ti20Zr21.5Al8Cu5Si3.5和Ni42Ti20Zr20.5Al8Cu5Si4.5合金中获得最大的约化玻璃转变温度Trg（=Tg／T1）及最大的过冷液相区△Tx（=Tx-Tg），分别为0．570和93K。Si显著增加玻璃形成能力主要是抑制引起异质形核的Ni（TiZr）相和（TiZr）（CuAl）2相的形成。室温压缩实验表明：Ni42Ti20Zr21.5Al8Cu5Si3.5合金抗压断裂强度为2724MPa。
利用DSC，DTA，XRD研究了NiTiZrAlCuSi块体非晶合金的形成。采用铜模铸造工艺使块体金属玻璃最大直径从Ni42Ti25Zr25Al8合金的小于0．5mm增加到Ni42Ti20Zr25Al8Cu5的1mm，然后增加到Ni42Ti20Zr21.5Al8Cu5Si3.5合金的4mm。在Ni42Ti20Zr21.5Al8Cu5Si3.5和Ni42Ti20Zr20.5Al8Cu5Si4.5合金中获得最大的约化玻璃转变温度Trg（=Tg／T1）及最大的过冷液相区△Tx（=Tx-Tg），分别为0．570和93K。Si显著增加玻璃形成能力主要是抑制引起异质形核的Ni（TiZr）相和（TiZr）（CuAl）2相的形成。室温压缩实验表明：Ni42Ti20Zr21.5Al8Cu5Si3.5合金抗压断裂强度为2724MPa。
2006, 35(9):1445-1448.
Abstract:
用水冷铜模吸铸法制备出名义成分（at％，下同）为Sm55-xCexCu15Ni10Al20（x=0，7，10，13，15，20，25）的合金样品。利用X射线衍射仪确定合金的结构，用示差扫描量热计（DSC）研究合金的玻璃转变、晶化和熔化行为。通过过冷液相区宽度△Tx和约化晶化温度Tx／Tm来表征Sm基大块非晶的玻璃形成能力，用Tg和Tx来表征其热稳定性。结果表明，Ce的加入使Sm基块体金属玻璃热稳定性降低，当Ce含量为10at％时，其玻璃形成能力最强，可以制备出φ5mm以上的块体金属玻璃，同时应用Miedema理论和等效电负性差△X讨论了该系列合金的玻璃形成能力。
用水冷铜模吸铸法制备出名义成分（at％，下同）为Sm55-xCexCu15Ni10Al20（x=0，7，10，13，15，20，25）的合金样品。利用X射线衍射仪确定合金的结构，用示差扫描量热计（DSC）研究合金的玻璃转变、晶化和熔化行为。通过过冷液相区宽度△Tx和约化晶化温度Tx／Tm来表征Sm基大块非晶的玻璃形成能力，用Tg和Tx来表征其热稳定性。结果表明，Ce的加入使Sm基块体金属玻璃热稳定性降低，当Ce含量为10at％时，其玻璃形成能力最强，可以制备出φ5mm以上的块体金属玻璃，同时应用Miedema理论和等效电负性差△X讨论了该系列合金的玻璃形成能力。
2006, 35(9):1449-1452.
Abstract:
以三氯化铝、氧氯化锆为原料，经离子交换溶胶-凝胶法在α-Al2O3中空纤维载体制备了Al2O3／ZrO2膜。应用XRD，SEM，BET等测试手段对膜的热稳定性、形貌、孔径及其分布进行了表征。XRD结果显示，复合膜的热稳定性比单一氧化铝或氧化锆有显著提高，在700℃～1000℃的范围内，复合膜的晶相均为四方相。扫描电镜结果表明，膜表面完整、无缺陷。气体渗透实验表明，担载膜具有一定的气体选择性，在0．1MPa下对H2／N2的分离因子分别为3．08。等温氮气吸附实验显示：700℃热处理后Al2O3／ZrO2复合膜呈双峰分布，在3．65nm和5．30nm处分别出现了极值点，孔容为0．12ml／g，比表面积为91．36m^2／g。
以三氯化铝、氧氯化锆为原料，经离子交换溶胶-凝胶法在α-Al2O3中空纤维载体制备了Al2O3／ZrO2膜。应用XRD，SEM，BET等测试手段对膜的热稳定性、形貌、孔径及其分布进行了表征。XRD结果显示，复合膜的热稳定性比单一氧化铝或氧化锆有显著提高，在700℃～1000℃的范围内，复合膜的晶相均为四方相。扫描电镜结果表明，膜表面完整、无缺陷。气体渗透实验表明，担载膜具有一定的气体选择性，在0．1MPa下对H2／N2的分离因子分别为3．08。等温氮气吸附实验显示：700℃热处理后Al2O3／ZrO2复合膜呈双峰分布，在3．65nm和5．30nm处分别出现了极值点，孔容为0．12ml／g，比表面积为91．36m^2／g。
23 The Effect of 15 wt% Mo Addition on the Microstructure and Mechanical Properties of MoSi2 Composite
2006, 35(9):1453-1456.
Abstract:
采用在常规模压生坯中浸渗Al的方法,研究了MoSi2+Mo反应熔渗Al后的显微组织和力学性能的变化情况.研究表明MoSi2坯体在1350℃反应浸渗Al可使抗弯强度高达737 MPa,其断裂韧性也可达到4.3 MPa·m1/2,远远高于热压单相材料;然而其相成分中存在残余的Si相和Al相将会阻碍其高温应用;在MoSi2坯体中加入Mo粉可以消除残余硅相;经过计算,当Mo添加量为15%(质量分数,下同)时,可以完全消除Si相,并使Al相达到最低,而其强度并不降低.同时SEM观察表明,添加15%Mo后其断口显示晶粒间絮状夹层变成颗粒状黑色相面积较未加入Mo粉时减小.从而进一步证实添加15%Mo产生的组织变化将有利于该材料的高温力学性能.
采用在常规模压生坯中浸渗Al的方法,研究了MoSi2+Mo反应熔渗Al后的显微组织和力学性能的变化情况.研究表明MoSi2坯体在1350℃反应浸渗Al可使抗弯强度高达737 MPa,其断裂韧性也可达到4.3 MPa·m1/2,远远高于热压单相材料;然而其相成分中存在残余的Si相和Al相将会阻碍其高温应用;在MoSi2坯体中加入Mo粉可以消除残余硅相;经过计算,当Mo添加量为15%(质量分数,下同)时,可以完全消除Si相,并使Al相达到最低,而其强度并不降低.同时SEM观察表明,添加15%Mo后其断口显示晶粒间絮状夹层变成颗粒状黑色相面积较未加入Mo粉时减小.从而进一步证实添加15%Mo产生的组织变化将有利于该材料的高温力学性能.
2006, 35(9):1457-1460.
Abstract:
Monodispersed nickel spheres with diameters ranging from 100 nm to 180 nm were prepared by microwave-assisted(MW)polyol method.The magnetic stripe domain structure in these nickel spheres was measured by magnetic force microscopy(MFM).Furthermore,in this work we reported the formation of core-shell structures of highly globular NicoreNiOshell which were synthesized from the Ni spheres,and the magnetic properties of the core-shell structures have been investigated.
Monodispersed nickel spheres with diameters ranging from 100 nm to 180 nm were prepared by microwave-assisted(MW)polyol method.The magnetic stripe domain structure in these nickel spheres was measured by magnetic force microscopy(MFM).Furthermore,in this work we reported the formation of core-shell structures of highly globular NicoreNiOshell which were synthesized from the Ni spheres,and the magnetic properties of the core-shell structures have been investigated.
2006, 35(9):1461-1465.
Abstract:
基于微观相场模型，模拟研究中间处理＋时效处理（1273K＋1073K）工艺对Ni-15．5％Al-10．5％Cr（原子分数，下同）合金沉淀机制和有序相体积分数的影响。研究发现：经过中间处理，合金沉淀机制为非经典形核长大；而单级时效时，沉淀机制为等成分有序化＋失稳分解混合机制。中间处理可得到尺寸较大的沉淀强化相γ-相，有序相体积分数和平均长程序参数有所提高，孕育期比单级时效延长。
基于微观相场模型，模拟研究中间处理＋时效处理（1273K＋1073K）工艺对Ni-15．5％Al-10．5％Cr（原子分数，下同）合金沉淀机制和有序相体积分数的影响。研究发现：经过中间处理，合金沉淀机制为非经典形核长大；而单级时效时，沉淀机制为等成分有序化＋失稳分解混合机制。中间处理可得到尺寸较大的沉淀强化相γ-相，有序相体积分数和平均长程序参数有所提高，孕育期比单级时效延长。
2006, 35(9):1466-1469.
Abstract:
采用真空中频感应炉熔炼＋真空电弧炉熔炼＋水冷铜模浇铸的工艺制备了Ni-Mn-Cr-Co-B钎焊料，确定了该钎焊料的热处理工艺参数和加工工艺条件，分析了工艺条件对材料组织和性能的影响。结果表明：Ni-Mn-Cr-Co-B合金在900℃加热后，应采用水冷的工艺，使第二相组织来不及析出，以便得到组织均匀的材料，从而使该合金硬度较低和塑性较好。该合金组织由基体γ-Ni（Mn，Cr，Co）固溶体、CrB相和Ni3B相组成。
采用真空中频感应炉熔炼＋真空电弧炉熔炼＋水冷铜模浇铸的工艺制备了Ni-Mn-Cr-Co-B钎焊料，确定了该钎焊料的热处理工艺参数和加工工艺条件，分析了工艺条件对材料组织和性能的影响。结果表明：Ni-Mn-Cr-Co-B合金在900℃加热后，应采用水冷的工艺，使第二相组织来不及析出，以便得到组织均匀的材料，从而使该合金硬度较低和塑性较好。该合金组织由基体γ-Ni（Mn，Cr，Co）固溶体、CrB相和Ni3B相组成。
2006, 35(9):1479-1482.
Abstract:
采用快速升温热压法制备了20%Grp/6061Al(质量分数,下同)复合材料并研究其摩擦磨损特性,通过光学显微镜和SEM分别观察了样品的组织结构及磨痕形貌,采用XRD分析了复合材料的相组成.研究表明快速升温热压能避免有害的界面反应,得到石墨颗粒分布均匀、界面干净且结合良好的Grp/6061Al复合材料,复合材料具有良好的摩擦磨损性能,T6处理能显著降低复合材料的摩擦系数和磨损率.在60 r/m转速、1 N～7 N载荷下,复合材料的摩擦系数随载荷的增大而减少,磨损量增大.T6热处理强化了界面结合,有利于石墨膜形成,降低了复合材料的摩擦系数,也显著减少了磨损率.热处理后,复合材料摩擦系数可达到0.16,磨损量平均减幅达50%,采用的最大载荷7 N下磨损率可减少到4.7×10-4 mm3/m.
采用快速升温热压法制备了20%Grp/6061Al(质量分数,下同)复合材料并研究其摩擦磨损特性,通过光学显微镜和SEM分别观察了样品的组织结构及磨痕形貌,采用XRD分析了复合材料的相组成.研究表明快速升温热压能避免有害的界面反应,得到石墨颗粒分布均匀、界面干净且结合良好的Grp/6061Al复合材料,复合材料具有良好的摩擦磨损性能,T6处理能显著降低复合材料的摩擦系数和磨损率.在60 r/m转速、1 N～7 N载荷下,复合材料的摩擦系数随载荷的增大而减少,磨损量增大.T6热处理强化了界面结合,有利于石墨膜形成,降低了复合材料的摩擦系数,也显著减少了磨损率.热处理后,复合材料摩擦系数可达到0.16,磨损量平均减幅达50%,采用的最大载荷7 N下磨损率可减少到4.7×10-4 mm3/m.
2006, 35(9):1483-1486.
Abstract:
研究了快淬工艺对无钴AB5型LaxMm1-x(NiMnSiAlFe)4.9(x=0,0.45,0.75,1.0)合金微观结构及电化学循环稳定性的影响.结果表明快淬处理显著改善合金的成分均匀性,使晶粒细化,并显著提高合金的循环稳定性.当淬速从0m/s增加到28 m/s时,经300次充放循环后,x=0.45合金的容量衰减率D从0.28 mAh/g·c-1(c代表一次循环)下降到0.13mAh/g·c-1;x=1.0合金的容量衰减率D从0.3mAh/g·c-1下降到0.14mAh/g·c-1.
研究了快淬工艺对无钴AB5型LaxMm1-x(NiMnSiAlFe)4.9(x=0,0.45,0.75,1.0)合金微观结构及电化学循环稳定性的影响.结果表明快淬处理显著改善合金的成分均匀性,使晶粒细化,并显著提高合金的循环稳定性.当淬速从0m/s增加到28 m/s时,经300次充放循环后,x=0.45合金的容量衰减率D从0.28 mAh/g·c-1(c代表一次循环)下降到0.13mAh/g·c-1;x=1.0合金的容量衰减率D从0.3mAh/g·c-1下降到0.14mAh/g·c-1.
2006, 35(9):1487-1491.
Abstract:
Fe3B/Nd2Fe14B nanocomposite magnetic powders were prepared by melt quenching and heat-treatment.The microstructure and crystallization behavior were studied by X-ray diffraction(XRD),differential thermal analysis(DTA),and vibrating sample magnetometer(VSM).It is found that the heating-up rate will affect the formation and decomposition of the phases at a certain extent for melt-spun Fe3B/Nd2Fe14B powders.It is confirmed that the overquenched Nd4.5Fe77B18.5 and Nd4Fe77Cr0.5B18.5 samples were decomposed to Fe3B/Nd2Fe14B via metastable Nd2Fe23B3 during annealing at 973 K for 7 min.Hci,Jr and(BH)max have been obviously improved for the samples annealed above 953 K for 10 min.The addition of Cr is effective for refining the grain size and increasing the intrinsic coercivity,resulting in an improvement of hard magnetic properties.
Fe3B/Nd2Fe14B nanocomposite magnetic powders were prepared by melt quenching and heat-treatment.The microstructure and crystallization behavior were studied by X-ray diffraction(XRD),differential thermal analysis(DTA),and vibrating sample magnetometer(VSM).It is found that the heating-up rate will affect the formation and decomposition of the phases at a certain extent for melt-spun Fe3B/Nd2Fe14B powders.It is confirmed that the overquenched Nd4.5Fe77B18.5 and Nd4Fe77Cr0.5B18.5 samples were decomposed to Fe3B/Nd2Fe14B via metastable Nd2Fe23B3 during annealing at 973 K for 7 min.Hci,Jr and(BH)max have been obviously improved for the samples annealed above 953 K for 10 min.The addition of Cr is effective for refining the grain size and increasing the intrinsic coercivity,resulting in an improvement of hard magnetic properties.
2006, 35(9):1492-1496.
Abstract:
The rotating anode target of X-Ray tube can be constituted with Mo diffusion bonded with graphite. The direct diffusion bonding of Mo and graphite without interlayer was conducted, and the microstructures and mechanical properties of the joints were investigated. Moreover, the effects of interlayer and its form on the interface reaction, the microstructures and the joint properties were inspected. The results indicated that the properties of the joints bonded without interlayer were inferior due to the hard and brittle carbide layer formation. The joint microstructures and properties could be improved with interlayer, especially when Ni was used as interlayer. The shear strength of the joint bonded with interlayer could be over the strength of the base material graphite. The different form of the interlayer, had effects on the microstructures and properties of the joints.
The rotating anode target of X-Ray tube can be constituted with Mo diffusion bonded with graphite. The direct diffusion bonding of Mo and graphite without interlayer was conducted, and the microstructures and mechanical properties of the joints were investigated. Moreover, the effects of interlayer and its form on the interface reaction, the microstructures and the joint properties were inspected. The results indicated that the properties of the joints bonded without interlayer were inferior due to the hard and brittle carbide layer formation. The joint microstructures and properties could be improved with interlayer, especially when Ni was used as interlayer. The shear strength of the joint bonded with interlayer could be over the strength of the base material graphite. The different form of the interlayer, had effects on the microstructures and properties of the joints.
2006, 35(9):1497-1500.
Abstract:
将直径为2.5mm,3.4mm,4.5mm,6mm,8mm的2DC/SiC复合材料铆钉和尺寸为φ12.8mm×6.5mm带孔件进行紧配合装配,然后对其沉积SiC,沉积时间300h,最终实现铆接。采用扫描电镜(SEM)及拉伸试验来测试连接情况。结果表明:当铆钉直径小于4.5mm时发生铆钉断裂现象,接头为脆性破坏;当直径大于4.5mm时发生铆钉拔出现象,接头为韧性破坏。但是直径越大被连接复合材料的性能损失越大,因此最佳的铆钉尺寸应稍大于4.5mm。
将直径为2.5mm,3.4mm,4.5mm,6mm,8mm的2DC/SiC复合材料铆钉和尺寸为φ12.8mm×6.5mm带孔件进行紧配合装配,然后对其沉积SiC,沉积时间300h,最终实现铆接。采用扫描电镜(SEM)及拉伸试验来测试连接情况。结果表明:当铆钉直径小于4.5mm时发生铆钉断裂现象,接头为脆性破坏;当直径大于4.5mm时发生铆钉拔出现象,接头为韧性破坏。但是直径越大被连接复合材料的性能损失越大,因此最佳的铆钉尺寸应稍大于4.5mm。
2006, 35(9):1501-1503.
Abstract:
采用电化学腐蚀的方法成功地制备了厚膜p型宏孔多孔硅。氢氟酸和二甲基甲酰胺按体积比1：4组成电化学腐蚀的溶液。通过在不同条件下制备的多组样品，得出了多孔硅生长速度与电流密度以及腐蚀厚度与腐蚀时间的函数关系。通过ESEM对所制样品进行了表面的截面形貌分析，得出30mA/cm^2-50mA/cm^2的阳极电流密度是制备高质量厚膜p型宏孔多孔硅的最佳条件。
采用电化学腐蚀的方法成功地制备了厚膜p型宏孔多孔硅。氢氟酸和二甲基甲酰胺按体积比1：4组成电化学腐蚀的溶液。通过在不同条件下制备的多组样品，得出了多孔硅生长速度与电流密度以及腐蚀厚度与腐蚀时间的函数关系。通过ESEM对所制样品进行了表面的截面形貌分析，得出30mA/cm^2-50mA/cm^2的阳极电流密度是制备高质量厚膜p型宏孔多孔硅的最佳条件。
2006, 35(9):1504-1508.
Abstract:
采用TSSG法生长出尺寸为15 mm×18 mm×25 mm的Er3+/Yb3+KY(WO4)2晶体,XRD分析表明所生长的晶体为β-Er/YbKYW.对晶体进行了TG-DTA分析,结果表明晶体的相转变温度和熔点分别为1031℃和1067℃.测得晶体的红外和拉曼光谱,并对峰值与相应的原子基团振动进行了指认.测得样品的吸收光谱,结果表明晶体在380 nm,525 nm,933 nm和981 nm处都存在较强的吸收峰,并计算出主峰981 nm的吸收截面积σabs=3.2×10-20cm2.分别用激发源为488 nm和978 nm对晶体进行了荧光光谱测试,并测得978 nm激发时荧光寿命为4.8 ms.对比分析表明在ErKYW中掺入Yb3+作为敏化离子是可行的,能够提高对泵浦光吸收,有利于得到更强的1540 nm的激光.
采用TSSG法生长出尺寸为15 mm×18 mm×25 mm的Er3+/Yb3+KY(WO4)2晶体,XRD分析表明所生长的晶体为β-Er/YbKYW.对晶体进行了TG-DTA分析,结果表明晶体的相转变温度和熔点分别为1031℃和1067℃.测得晶体的红外和拉曼光谱,并对峰值与相应的原子基团振动进行了指认.测得样品的吸收光谱,结果表明晶体在380 nm,525 nm,933 nm和981 nm处都存在较强的吸收峰,并计算出主峰981 nm的吸收截面积σabs=3.2×10-20cm2.分别用激发源为488 nm和978 nm对晶体进行了荧光光谱测试,并测得978 nm激发时荧光寿命为4.8 ms.对比分析表明在ErKYW中掺入Yb3+作为敏化离子是可行的,能够提高对泵浦光吸收,有利于得到更强的1540 nm的激光.
2006, 35(9):1509-1512.
Abstract:
This paper introduces the fabrication method of W/Cu-FGM by Vacuum Plasma Spraying & Electron Beam Welding.Specimen could endure 20 s pluses under heat fluxes of 8 MW/m2.No damages appeared in the tested specimens which endured 26 s,22 s,20 s pluses under 2.5 MW/m2,4.5 MW/m2,6 MW/m2,respectively.Good performances were presented in the fatigue tests of the specimens.The specimens could endure 70 cycles fatigue under 6 MW/m2 and 20 s pluses;No damages appeared after the specimens were subject to 100 cyles fatigue test under 2.5 MW/m2,30 s and 4.5 MW/m2,25 s.Crack began to come into being during 90 cycles fatigue at the heat fluxes of 6 MW/m2,enduring 20 s.The specimen was analyzed by EDS.Impurities and pores were observed.
This paper introduces the fabrication method of W/Cu-FGM by Vacuum Plasma Spraying & Electron Beam Welding.Specimen could endure 20 s pluses under heat fluxes of 8 MW/m2.No damages appeared in the tested specimens which endured 26 s,22 s,20 s pluses under 2.5 MW/m2,4.5 MW/m2,6 MW/m2,respectively.Good performances were presented in the fatigue tests of the specimens.The specimens could endure 70 cycles fatigue under 6 MW/m2 and 20 s pluses;No damages appeared after the specimens were subject to 100 cyles fatigue test under 2.5 MW/m2,30 s and 4.5 MW/m2,25 s.Crack began to come into being during 90 cycles fatigue at the heat fluxes of 6 MW/m2,enduring 20 s.The specimen was analyzed by EDS.Impurities and pores were observed.
