Volume 34,Issue 7,2005 Table of Contents
2005, 34(7).
Abstract:
较详细地研究了Er2-xCexFe17化合物的结构、磁性和磁熵变。结果表明,轻稀土Ce的掺入虽然没有明显改变Er2Fe17化合物的相结构及其晶格常数,但改变了Er次晶格与Fe次晶格之间的耦合系数,使仍为Th2Ni17型六方结构的Er2-xCexFe17化合物的居里温度可通过成分微调使其处在室温附近。Er2-xCexFe17化合物的λ形(-?SM)-T曲线表明其在居里点附近发生的相变属于二级相变,它使化合物可在较宽温区范围内保持较大的磁熵变。Er2-xCexFe17化合物在x=0.05~0.1范围内具有较大的磁熵变,其在2.0T和5.0T外场下的最大磁熵变达到金属Gd的40%~50%,且其化学性质稳定、制冷温区宽、价格低廉,是一类性价比较高、应用潜力较大的新型低场室温磁制冷工质材料。
较详细地研究了Er2-xCexFe17化合物的结构、磁性和磁熵变。结果表明,轻稀土Ce的掺入虽然没有明显改变Er2Fe17化合物的相结构及其晶格常数,但改变了Er次晶格与Fe次晶格之间的耦合系数,使仍为Th2Ni17型六方结构的Er2-xCexFe17化合物的居里温度可通过成分微调使其处在室温附近。Er2-xCexFe17化合物的λ形(-?SM)-T曲线表明其在居里点附近发生的相变属于二级相变,它使化合物可在较宽温区范围内保持较大的磁熵变。Er2-xCexFe17化合物在x=0.05~0.1范围内具有较大的磁熵变,其在2.0T和5.0T外场下的最大磁熵变达到金属Gd的40%~50%,且其化学性质稳定、制冷温区宽、价格低廉,是一类性价比较高、应用潜力较大的新型低场室温磁制冷工质材料。
2005, 34(7):1009-1012.
Abstract:
Both CrN hard coatings and CuNiIn solid lubricating films were produced on the titanium alloy substrate by the ion beam enhanced deposition (IBED) technique. The electrochemical corrosion behavior and galvanic corrosion sensitivity of the IBED films and titanium alloy in NaCl solution were studied by using electrochemical measurement methods. The oxidation resistance of the IBED films was evaluated by the elevated temperature static oxidation method. The results show that both the electrochemical corrosion resistance and the oxidation resistance of IBEDD CuNiIn film are better than those of bulk copper. IBED CuNiIn film is contact compatible with titanium alloy substrate in Cl- solution. IBED CrN film has good corrosion resistance compared with the titanium alloy in both Cl- solution and HCl + HF mixed acid solution, it can directly contact with titanium alloy in Cl- solution. The oxidation resistance of CrN film is better than that of the titanium alloy substrate.
Both CrN hard coatings and CuNiIn solid lubricating films were produced on the titanium alloy substrate by the ion beam enhanced deposition (IBED) technique. The electrochemical corrosion behavior and galvanic corrosion sensitivity of the IBED films and titanium alloy in NaCl solution were studied by using electrochemical measurement methods. The oxidation resistance of the IBED films was evaluated by the elevated temperature static oxidation method. The results show that both the electrochemical corrosion resistance and the oxidation resistance of IBEDD CuNiIn film are better than those of bulk copper. IBED CuNiIn film is contact compatible with titanium alloy substrate in Cl- solution. IBED CrN film has good corrosion resistance compared with the titanium alloy in both Cl- solution and HCl + HF mixed acid solution, it can directly contact with titanium alloy in Cl- solution. The oxidation resistance of CrN film is better than that of the titanium alloy substrate.
2005, 34(7):1013-1016.
Abstract:
研究了Ce对镁及镁合金晶粒细化效果和力学性能的影响。结果表明：纯镁结晶时易形成粗大的柱状晶和扇形晶，加入微量稀土元素Ce后，晶粒被明显细化，柱状晶全部转化成等轴晶。在AZ31合金中添加微量稀十元素Ce，晶粒由未细化前的约300μm下降到约30μm。稀土Ce在镁及AZ31合金中的固溶度很小，在凝固过程中固／液界面前沿Ce容易富集引起成分过冷形成新形核带导致晶粒细化。凝固过程中溶质再分配造成固液界面前沿成分过冷度增大是稀土元素细化镁及镁合金的主要机理。
研究了Ce对镁及镁合金晶粒细化效果和力学性能的影响。结果表明：纯镁结晶时易形成粗大的柱状晶和扇形晶，加入微量稀土元素Ce后，晶粒被明显细化，柱状晶全部转化成等轴晶。在AZ31合金中添加微量稀十元素Ce，晶粒由未细化前的约300μm下降到约30μm。稀土Ce在镁及AZ31合金中的固溶度很小，在凝固过程中固／液界面前沿Ce容易富集引起成分过冷形成新形核带导致晶粒细化。凝固过程中溶质再分配造成固液界面前沿成分过冷度增大是稀土元素细化镁及镁合金的主要机理。
2005, 34(7):1017-1020.
Abstract:
The absorption and desorption kinetics of the metal hydrogen storage materials are related with the grain sizes to some extent. By means of the absorption and desorption kinetics equations, the effects of the grain sizes of Mg-Ni-MnO2 hydrogen storage materials on their absorption and desorption kinetics are calculated. The results show that the reaction rates of absorption and desorption are greatly different among the Mg-Ni-MnO2 hydrogen storage materials with different particle sizes; the smaller the particle size is, the better the absorption and desorption kinetic. The experimental results of the absorption and desorption kinetics of the Mg-Ni-MnO2 materials prove the kinetic equations to be rational.
The absorption and desorption kinetics of the metal hydrogen storage materials are related with the grain sizes to some extent. By means of the absorption and desorption kinetics equations, the effects of the grain sizes of Mg-Ni-MnO2 hydrogen storage materials on their absorption and desorption kinetics are calculated. The results show that the reaction rates of absorption and desorption are greatly different among the Mg-Ni-MnO2 hydrogen storage materials with different particle sizes; the smaller the particle size is, the better the absorption and desorption kinetic. The experimental results of the absorption and desorption kinetics of the Mg-Ni-MnO2 materials prove the kinetic equations to be rational.
2005, 34(7):1021-1024.
Abstract:
搅拌摩擦焊接显微组织的一个显著特征就是焊核(Weld Nugget)的形成。采用AZ31镁合金为母材，通过金相和透射电镜分析搅拌摩擦焊接焊核的形成机制及接头不同区域的显微组织特征，并建立AZ31镁合金搅拌摩擦焊接的组织演变模型。结果显示，紧靠轴肩生成厚度约为37gm～47gm细密组织层。机械热影响区存在部分动态再结晶和较明显的塑性变形晶粒。焊缝底部有一厚约100gm～130gm的粗大组织层。熔核区的组织比较细小，沿厚度方向晶粒大小不均匀。同时提出一个焊核晶粒细化的简易模型，分析认为焊接过程中热过程和热机械搅拌作用对FSW接头组织的形成起决定性作用。
搅拌摩擦焊接显微组织的一个显著特征就是焊核(Weld Nugget)的形成。采用AZ31镁合金为母材，通过金相和透射电镜分析搅拌摩擦焊接焊核的形成机制及接头不同区域的显微组织特征，并建立AZ31镁合金搅拌摩擦焊接的组织演变模型。结果显示，紧靠轴肩生成厚度约为37gm～47gm细密组织层。机械热影响区存在部分动态再结晶和较明显的塑性变形晶粒。焊缝底部有一厚约100gm～130gm的粗大组织层。熔核区的组织比较细小，沿厚度方向晶粒大小不均匀。同时提出一个焊核晶粒细化的简易模型，分析认为焊接过程中热过程和热机械搅拌作用对FSW接头组织的形成起决定性作用。
2005, 34(7):1025-1028.
Abstract:
以2090 Ce合金为研究对象，对不同时效时间的室温拉伸断口进行了半定量分析，探讨了拉伸性能对断裂特征的响应关系，重点分析合金分层裂纹的形成过程。研究表明：2090 Ce合金的断裂方式以韧窝、分层开裂和沿亚晶界开裂3种为主，随时效时间的延长，韧窝、分层开裂逐渐减少，沿亚晶界开裂比例逐渐加大：分层开裂程度与时效程度有密切关系：分层开裂过程与试样内部受力状态、晶界状态有密切关系。分层最先发生在试样中心，随后在二分之一、四分之一……处反复发生，最终将试样分割成一系列平行的薄板。时效后期由于亚晶界的弱化，使裂纹倾向沿亚晶界扩展，从而抑制分层开裂的发生，同时导致合金强度，尤其是塑性的下降。
以2090 Ce合金为研究对象，对不同时效时间的室温拉伸断口进行了半定量分析，探讨了拉伸性能对断裂特征的响应关系，重点分析合金分层裂纹的形成过程。研究表明：2090 Ce合金的断裂方式以韧窝、分层开裂和沿亚晶界开裂3种为主，随时效时间的延长，韧窝、分层开裂逐渐减少，沿亚晶界开裂比例逐渐加大：分层开裂程度与时效程度有密切关系：分层开裂过程与试样内部受力状态、晶界状态有密切关系。分层最先发生在试样中心，随后在二分之一、四分之一……处反复发生，最终将试样分割成一系列平行的薄板。时效后期由于亚晶界的弱化，使裂纹倾向沿亚晶界扩展，从而抑制分层开裂的发生，同时导致合金强度，尤其是塑性的下降。
2005, 34(7):1033-1035.
Abstract:
The solidification behaviors of nonferromagnetic Al3Ni precipitated phase in Al-8%Ni alloy with a high magnetic field applied have been studied experimentally. It is found that the magnetic field induces the crystals of Al3Ni phase to orient with their c-axes parallel to the field and the long axes of the crystals are perpendicular to their c-axes. There are several Al3Ni congregation planes parallel with each other, which are perpendicular to the field, that is, regular Al3Ni laminated alignment structure is formed in the alloy. In the planes, there are several big Al3Ni congregations, in the inner part of which there are aligned Al3Ni crystals.
The solidification behaviors of nonferromagnetic Al3Ni precipitated phase in Al-8%Ni alloy with a high magnetic field applied have been studied experimentally. It is found that the magnetic field induces the crystals of Al3Ni phase to orient with their c-axes parallel to the field and the long axes of the crystals are perpendicular to their c-axes. There are several Al3Ni congregation planes parallel with each other, which are perpendicular to the field, that is, regular Al3Ni laminated alignment structure is formed in the alloy. In the planes, there are several big Al3Ni congregations, in the inner part of which there are aligned Al3Ni crystals.
2005, 34(7):1036-1038.
Abstract:
研究了Zn对2195铝锂合金在不同热处理状态(T8，T6)下的显微组织和拉伸性能的影响。结果表明：Zn的存在明显促进了T1相的析出和弥散分布，而且有球形颗粒状含Zn相析出，使合金强度提高：但Zn的加入不改变2195合金的断裂机制，且使合金塑性略有下降。
研究了Zn对2195铝锂合金在不同热处理状态(T8，T6)下的显微组织和拉伸性能的影响。结果表明：Zn的存在明显促进了T1相的析出和弥散分布，而且有球形颗粒状含Zn相析出，使合金强度提高：但Zn的加入不改变2195合金的断裂机制，且使合金塑性略有下降。
2005, 34(7):1039-1042.
Abstract:
以Cu2O为氧化剂，采用Cu-Al合金粉末内氧化及后续的粉末冶金法制备了Al2O3／Cu复合材料。并将不同Al2O3含量的试样进行不同变形量的冷拔处理，在氮气保护下进行高温退火处理(700℃～1050℃，1h)。研究了硬度随退火温度的变化规律，观察了显微组织。结果表明：在铜基体中弥散分布着纳米级的Al2O3颗粒：经900℃，1h退火后Al2O3／Cu复合材料的硬度可保持室温的87％以上；其再结晶温度高达1000℃；变形量和Al2O3含量增加均使硬度提高，但对软化和再结晶温度影响不大。
以Cu2O为氧化剂，采用Cu-Al合金粉末内氧化及后续的粉末冶金法制备了Al2O3／Cu复合材料。并将不同Al2O3含量的试样进行不同变形量的冷拔处理，在氮气保护下进行高温退火处理(700℃～1050℃，1h)。研究了硬度随退火温度的变化规律，观察了显微组织。结果表明：在铜基体中弥散分布着纳米级的Al2O3颗粒：经900℃，1h退火后Al2O3／Cu复合材料的硬度可保持室温的87％以上；其再结晶温度高达1000℃；变形量和Al2O3含量增加均使硬度提高，但对软化和再结晶温度影响不大。
2005, 34(7):1043-1046.
Abstract:
用K-RE对Fe-5％V-5％W-5％Mo-5％Cr-3％Nb-2％Co-2％C合金变质处理，使凝固组织发生了明显的变化，不仅碳化物和基体组织明显细化，还出现共晶碳化物断网现象，产生了较多的小块状和颗粒状碳化物。经K-RE变质处理Fe-V-W-Mo合金加热温度950℃时，碳化物断网明显，加热温度1000℃时，多数碳化物已断网，并出现了数量较多的颗粒状碳化物，加热温度1050℃时，碳化物网状组织全部消失，大部分碳化物变成了球状组织。
用K-RE对Fe-5％V-5％W-5％Mo-5％Cr-3％Nb-2％Co-2％C合金变质处理，使凝固组织发生了明显的变化，不仅碳化物和基体组织明显细化，还出现共晶碳化物断网现象，产生了较多的小块状和颗粒状碳化物。经K-RE变质处理Fe-V-W-Mo合金加热温度950℃时，碳化物断网明显，加热温度1000℃时，多数碳化物已断网，并出现了数量较多的颗粒状碳化物，加热温度1050℃时，碳化物网状组织全部消失，大部分碳化物变成了球状组织。
2005, 34(7):1047-1050.
Abstract:
The effect of rapid quenching on phase structure and hydrogen storage performance of Ti-28V-15Mn-10Cr alloy is investigated. X-ray diffraction (XRD) results show that two phases of BCC and C14 Laves of the as-cast alloy are transformed into a single BCC phase after rapid quenching treatment. The lattice parameters of the alloy increase with increasing of quenching rate. It results in a flatter hydrogen absorption-desorption plateau and a lower hydrogen absorption-desorption plateau pressure. With increasing quenching rate,the activation of Ti-28V-15Mn-10Cr alloy becomes worse.
The effect of rapid quenching on phase structure and hydrogen storage performance of Ti-28V-15Mn-10Cr alloy is investigated. X-ray diffraction (XRD) results show that two phases of BCC and C14 Laves of the as-cast alloy are transformed into a single BCC phase after rapid quenching treatment. The lattice parameters of the alloy increase with increasing of quenching rate. It results in a flatter hydrogen absorption-desorption plateau and a lower hydrogen absorption-desorption plateau pressure. With increasing quenching rate,the activation of Ti-28V-15Mn-10Cr alloy becomes worse.
12 Effect of Cr Addition on
Crystallization Behavior and Magnetic Properties of Nanocomposite Nd2Fe14B/
2005, 34(7):1051-1054.
Abstract:
采用熔体快淬及晶化处理工艺制备Nd11Fe72-xCo8V1.5CrB7.5(x=0，1)纳米晶合金。研究了添加Cr对合金晶化行为和磁性能的影响。结果表明，添加Cr提高了软磁相α-Fe和硬磁相Nd2Fe14B的形成温度，降低了硬磁相Nd2Fe14B的居里温度。同时，添加Cr可细化两相晶粒，提高内禀矫顽力，从而提高最大磁能积。
采用熔体快淬及晶化处理工艺制备Nd11Fe72-xCo8V1.5CrB7.5(x=0，1)纳米晶合金。研究了添加Cr对合金晶化行为和磁性能的影响。结果表明，添加Cr提高了软磁相α-Fe和硬磁相Nd2Fe14B的形成温度，降低了硬磁相Nd2Fe14B的居里温度。同时，添加Cr可细化两相晶粒，提高内禀矫顽力，从而提高最大磁能积。
2005, 34(7):1055-1057.
Abstract:
采用熔体快淬及晶化热处理工艺制备Nd10Fe75Co5Zr3Cr0.5B6 5纳米晶合金.快淬薄片(17m·s-1)在710℃,4 min晶化处理后,晶粒尺寸为50 nm～60 nm.该快淬薄片经710℃,4min晶化处理后制成的粘结磁体的磁性能为Br=0.67 T,JHc=707 kA·m-1和(BH)max=74 kJ·m-3.
采用熔体快淬及晶化热处理工艺制备Nd10Fe75Co5Zr3Cr0.5B6 5纳米晶合金.快淬薄片(17m·s-1)在710℃,4 min晶化处理后,晶粒尺寸为50 nm～60 nm.该快淬薄片经710℃,4min晶化处理后制成的粘结磁体的磁性能为Br=0.67 T,JHc=707 kA·m-1和(BH)max=74 kJ·m-3.
Hou Xueling
,
Kong Junfeng
,
Jin Hongming
,
Li Zengfeng
,
Pang Wei
,
Shi Yongjin
,
Luo Jianjun
,
Tan Ping
,
Zhang Hanliang
2005, 34(7):1058-1060.
Abstract:
采用SEM和XRD对Nd13Fe81.5B5.5合金氢化-歧化-脱氢过程中相结构和组织形貌的变化进行了观测分析，结果表明：非受热的Nd13Fe81.5B5.5合金的吸氢只能在富钕相的品界上进行，吸氢的过程伴随着热量的释放。加热后的Nd13Fe81.5B5.5合金吸氢不仪沿着Nd13Fe81.5B5.5富钕相品界进行，而且也能在其品格内进行。合金吸氢后牛成物丰相为NdH2.9和α-Fe，还有微量的Fe2B和Fe2Nd，吸氢的过程伴随着大量热的释放，Nd13Fe81.5B5.5合金的吸氢温度为700℃，在730℃～800℃的范围内脱氢，在此工艺条件下，能获得高质量的氢化物。
采用SEM和XRD对Nd13Fe81.5B5.5合金氢化-歧化-脱氢过程中相结构和组织形貌的变化进行了观测分析，结果表明：非受热的Nd13Fe81.5B5.5合金的吸氢只能在富钕相的品界上进行，吸氢的过程伴随着热量的释放。加热后的Nd13Fe81.5B5.5合金吸氢不仪沿着Nd13Fe81.5B5.5富钕相品界进行，而且也能在其品格内进行。合金吸氢后牛成物丰相为NdH2.9和α-Fe，还有微量的Fe2B和Fe2Nd，吸氢的过程伴随着大量热的释放，Nd13Fe81.5B5.5合金的吸氢温度为700℃，在730℃～800℃的范围内脱氢，在此工艺条件下，能获得高质量的氢化物。
2005, 34(7):1061-1064.
Abstract:
通过采用电弧炉冶炼、HDDR及氮化的方法,对Sm2Fe17型合金及其氮化物的组织形貌、物相及磁性能进行研究发现,多补偿添加25%钐可使Sm2Fe17型合金退火后的α-Fe含量小于2%.HDDR后的粉末颗粒表面由蜂窝状孔洞、密堆积小颗粒及弥散细小颗粒组成.不同次数HDDR循环处理后的主相均表现为与退火后相同的Sm2Fe17结构及易面磁化.HDDR后α-Fe的含量增加,单胞体积膨胀△V/V0.35%.氮化后Sm2Fe17晶格膨胀形成Sm2Fe17Nx主相,α-Fe相膨胀小,氮化增加α-Fe含量,多补偿Sm和延长氮化时间对减少α-Fe含量有利.随着氮化时间的延长,粉末中的氮含量增加,而且细粉氮化速度快,其中Sm12.8Fe87.2细粉氮化速度最快.补偿足够的钐可提高磁性能,从提高矫顽力角度看,多添加25%Sm与40%Sm效果相当,但从提高剩磁角度看,多添加钐到40%更好.
通过采用电弧炉冶炼、HDDR及氮化的方法,对Sm2Fe17型合金及其氮化物的组织形貌、物相及磁性能进行研究发现,多补偿添加25%钐可使Sm2Fe17型合金退火后的α-Fe含量小于2%.HDDR后的粉末颗粒表面由蜂窝状孔洞、密堆积小颗粒及弥散细小颗粒组成.不同次数HDDR循环处理后的主相均表现为与退火后相同的Sm2Fe17结构及易面磁化.HDDR后α-Fe的含量增加,单胞体积膨胀△V/V0.35%.氮化后Sm2Fe17晶格膨胀形成Sm2Fe17Nx主相,α-Fe相膨胀小,氮化增加α-Fe含量,多补偿Sm和延长氮化时间对减少α-Fe含量有利.随着氮化时间的延长,粉末中的氮含量增加,而且细粉氮化速度快,其中Sm12.8Fe87.2细粉氮化速度最快.补偿足够的钐可提高磁性能,从提高矫顽力角度看,多添加25%Sm与40%Sm效果相当,但从提高剩磁角度看,多添加钐到40%更好.
2005, 34(7):1065-1068.
Abstract:
A series of Er2-xPrxFe17 alloys were prepared by the arc melting under the purified argon atmosphere. By means of X-ray diffraction pattern and SQUID magnetometer, the structure and magnetic entropy changes in Er2-xPrxFe17 alloys were investigated. The results show that the crystal structure is Th2Ni17-type hexagonal for Er2-xPrxFe17 alloys; the Curie temperature of Er2-xPrxFe17 alloys can be shifted to the room temperature around by a small adjustment of composition. Magnetic entropy changes (-?SM) near Curie temperature are relatively large in a comparatively wide temperature range for Er2-xPrxFe17 alloys. Er2-xPrxFe17 alloys are provided with great potential in application for the room-temperature magnetic refrigeration
A series of Er2-xPrxFe17 alloys were prepared by the arc melting under the purified argon atmosphere. By means of X-ray diffraction pattern and SQUID magnetometer, the structure and magnetic entropy changes in Er2-xPrxFe17 alloys were investigated. The results show that the crystal structure is Th2Ni17-type hexagonal for Er2-xPrxFe17 alloys; the Curie temperature of Er2-xPrxFe17 alloys can be shifted to the room temperature around by a small adjustment of composition. Magnetic entropy changes (-?SM) near Curie temperature are relatively large in a comparatively wide temperature range for Er2-xPrxFe17 alloys. Er2-xPrxFe17 alloys are provided with great potential in application for the room-temperature magnetic refrigeration
2005, 34(7):1069-1072.
Abstract:
较详细地研究了Er2-xCexFe17化合物的结构、磁性和磁熵变。结果表明，轻稀土Ce的掺入虽然没有明显改变Er2Fe17化合物的相结构及其晶格常数，但改变了Er次晶格与Fe次晶格之间的耦合系数，使仍为Th2Ni17型六方结构的Er2-xCexFe17化合物的居里温度可通过成分微调使其处在室温附近。Er2-xCexFe17化合物的λ形(-△SM)-T曲线表明其在居里点附近发生的相变属于二级相变，它使化合物可在较宽温区范围内保持较大的磁熵变。Er2-xCexFe17化合物在x=0．05-0．1范围内具有较大的磁熵变，其在2．0T和5．0T外场下的最大磁熵变达到金属Gd的40%～50％，且其化学性质稳定、制冷温区宽、价格低廉，是一类性价比较高、应用潜力较大的新型低场室温磁制冷工质材料。
较详细地研究了Er2-xCexFe17化合物的结构、磁性和磁熵变。结果表明，轻稀土Ce的掺入虽然没有明显改变Er2Fe17化合物的相结构及其晶格常数，但改变了Er次晶格与Fe次晶格之间的耦合系数，使仍为Th2Ni17型六方结构的Er2-xCexFe17化合物的居里温度可通过成分微调使其处在室温附近。Er2-xCexFe17化合物的λ形(-△SM)-T曲线表明其在居里点附近发生的相变属于二级相变，它使化合物可在较宽温区范围内保持较大的磁熵变。Er2-xCexFe17化合物在x=0．05-0．1范围内具有较大的磁熵变，其在2．0T和5．0T外场下的最大磁熵变达到金属Gd的40%～50％，且其化学性质稳定、制冷温区宽、价格低廉，是一类性价比较高、应用潜力较大的新型低场室温磁制冷工质材料。
2005, 34(7):1073-1076.
Abstract:
采用二氧化硅／碳化硅复合靶，用射频磁控共溅射技术和后高温退火的方法在Si(111)衬底上制备了碳化硅纳米颗粒／二氧化硅基质(nc-SiC／SiO2)镶嵌结构薄膜材料，用X射线衍射(XRD)，傅里叶红外吸收(FTIR)，扫描电子显微镜(SEM)和光致发光(PL)实验分析了薄膜的微结构以及光致发光特性。结果表明：样品薄膜经高温退火后，部分无定形SiC发生晶化，形成β-SiC纳米颗粒而较均匀地镶嵌在SiO2基质中。以280nm波长光激发薄膜表面，有较强的365nm的紫外光发射以及458nm和490nm处的蓝光发射，其发光强度随退火温度的升高显著增强，发光归结为薄膜中与Si-O相关的缺陷形成的发光中心。
采用二氧化硅／碳化硅复合靶，用射频磁控共溅射技术和后高温退火的方法在Si(111)衬底上制备了碳化硅纳米颗粒／二氧化硅基质(nc-SiC／SiO2)镶嵌结构薄膜材料，用X射线衍射(XRD)，傅里叶红外吸收(FTIR)，扫描电子显微镜(SEM)和光致发光(PL)实验分析了薄膜的微结构以及光致发光特性。结果表明：样品薄膜经高温退火后，部分无定形SiC发生晶化，形成β-SiC纳米颗粒而较均匀地镶嵌在SiO2基质中。以280nm波长光激发薄膜表面，有较强的365nm的紫外光发射以及458nm和490nm处的蓝光发射，其发光强度随退火温度的升高显著增强，发光归结为薄膜中与Si-O相关的缺陷形成的发光中心。
2005, 34(7):1077-1080.
Abstract:
Thin VOx films were prepared by magnetron sputtering onto p-Si(100) substrates. X-ray diffraction (XRD), atomic force microscope(AFM) and four-point probe method were employed to study the influence of the preparation parameters on the phase composition and resistance-temperature characteristic of VOx. The thermal stability of the films was also investigated. The results show that VOx films prepared by this method have relatively high temperature coefficient of resistance (TCR) and perfect thermal stability. They are promising to be used as thermal sensor materials in the microbolometer.
Thin VOx films were prepared by magnetron sputtering onto p-Si(100) substrates. X-ray diffraction (XRD), atomic force microscope(AFM) and four-point probe method were employed to study the influence of the preparation parameters on the phase composition and resistance-temperature characteristic of VOx. The thermal stability of the films was also investigated. The results show that VOx films prepared by this method have relatively high temperature coefficient of resistance (TCR) and perfect thermal stability. They are promising to be used as thermal sensor materials in the microbolometer.
2005, 34(7):1081-1084.
Abstract:
应用循环伏安法研究了聚合前驱体热分解法制备的Ti／TiO2膜电极在pH=1的H2SO4溶液和pH=14的NaOH溶液中的电化学活化表面积。结果表明，相同条件下制备的Ti／TiO2膜电极在H2SO4溶液中的伏安电荷容量要远远高于在NaOH溶液中的伏安电荷容量，电极在不同pH值溶液中的内电化学活化表面积又远远高于外电化学活化表面积。因此电极表面活化表面积的大小与电极的结构以及溶液的pH值有关。
应用循环伏安法研究了聚合前驱体热分解法制备的Ti／TiO2膜电极在pH=1的H2SO4溶液和pH=14的NaOH溶液中的电化学活化表面积。结果表明，相同条件下制备的Ti／TiO2膜电极在H2SO4溶液中的伏安电荷容量要远远高于在NaOH溶液中的伏安电荷容量，电极在不同pH值溶液中的内电化学活化表面积又远远高于外电化学活化表面积。因此电极表面活化表面积的大小与电极的结构以及溶液的pH值有关。
2005, 34(7):1085-1088.
Abstract:
以Ce(NO3)3·6HzO为铈源,(NH4)2CO3·H2O为沉淀剂,并加入一定量表面活性剂PEG4000,采用液相沉淀法制备前驱体Ce2(CO3)3·H2O,前驱体经热处理合成纳米CeO2.根据XRD线宽法研究了纳米CeO2热处理过程的晶粒生长动力学,结果表明随焙烧温度升高,CeO2晶粒尺寸显著增大;300℃下焙烧时间对CeO2晶粒尺寸影响不明显,700℃下CeO2晶粒随焙烧时间延长而长大,且焙烧初期粒径增长较快,超过180 min后增长速率变慢;700℃时CeO2晶粒生长指数为5,即符合5次方动力学方程,晶粒生长速率常数为1.986 5×104 nm5/min;由于纳米尺寸效应,使得CeO2晶粒生长活化能在低温区和高温区不同,低于400℃时为25.64 kJ/mol,高于400℃时为87.64 kJ/mol;认为热处理过程CeO2的晶粒生长为扩散生长机制.
以Ce(NO3)3·6HzO为铈源,(NH4)2CO3·H2O为沉淀剂,并加入一定量表面活性剂PEG4000,采用液相沉淀法制备前驱体Ce2(CO3)3·H2O,前驱体经热处理合成纳米CeO2.根据XRD线宽法研究了纳米CeO2热处理过程的晶粒生长动力学,结果表明随焙烧温度升高,CeO2晶粒尺寸显著增大;300℃下焙烧时间对CeO2晶粒尺寸影响不明显,700℃下CeO2晶粒随焙烧时间延长而长大,且焙烧初期粒径增长较快,超过180 min后增长速率变慢;700℃时CeO2晶粒生长指数为5,即符合5次方动力学方程,晶粒生长速率常数为1.986 5×104 nm5/min;由于纳米尺寸效应,使得CeO2晶粒生长活化能在低温区和高温区不同,低于400℃时为25.64 kJ/mol,高于400℃时为87.64 kJ/mol;认为热处理过程CeO2的晶粒生长为扩散生长机制.
2005, 34(7):1089-1093.
Abstract:
以TiCl4和O2为反应体系，采用高频等离子化学气相沉积(HF-PCVD)法制备了晶化完整的锐钛和金红石混晶型TiO2纳米晶，球形体的晶粒分散性良好，分布较为均匀：研究了控制粒径大小和晶相组成的关键反应条件。XPS，TEM，XRD结果显示：增加TiCl4进料量、延长停留时间均利于锐钛相向金红石相转化，但粒径有所增大：添加A1C13使金红石相含量较未掺杂时有较大幅度提高，且粒径随掺铝量增加而减小。本实验条件下，TiO2纳米晶的粒径为25nm～60nm，金红石相含量在12．O％～53．6％间可控。
以TiCl4和O2为反应体系，采用高频等离子化学气相沉积(HF-PCVD)法制备了晶化完整的锐钛和金红石混晶型TiO2纳米晶，球形体的晶粒分散性良好，分布较为均匀：研究了控制粒径大小和晶相组成的关键反应条件。XPS，TEM，XRD结果显示：增加TiCl4进料量、延长停留时间均利于锐钛相向金红石相转化，但粒径有所增大：添加A1C13使金红石相含量较未掺杂时有较大幅度提高，且粒径随掺铝量增加而减小。本实验条件下，TiO2纳米晶的粒径为25nm～60nm，金红石相含量在12．O％～53．6％间可控。
2005, 34(7):1094-1097.
Abstract:
The compound nanoparticle of TiO2 doped with rare earth ions Y3+ was prepared under the optimum condition of preparing nanoparticle TiO2 with sol-gel processing. TiO2 and doped TiO2 were both characterized by XRD, TEM and DRS. The experiments of photocatalytic degradation phenol was used to investigate the activity of Y3+/TiO2 and its effect on the reaction process. The XRD results show that TiO2 and doped TiO2 are the mixture of anatase and rutile, and the ratio of anatase to rutile was 3:1; doping can retard the development of grain size of TiO2 and decrease the diameter of TiO2 to about 10nm. DRS are used to investigate the ability of absorbing light and the shift of spectrums of TiO2 and doped TiO2. The results show doping makes the light absorption increase and the spectrums of 1.5Y3+/TiO2 and 3.0Y3+/TiO2 both show red shift. The results of experiment of photocatalytic degradation of phenol show that the optimum doping content is wt(Y3+)=1.5%, and the photocatalytic degradation ratio of phenol increases by about 20% compared with the undoped TiO2.
The compound nanoparticle of TiO2 doped with rare earth ions Y3+ was prepared under the optimum condition of preparing nanoparticle TiO2 with sol-gel processing. TiO2 and doped TiO2 were both characterized by XRD, TEM and DRS. The experiments of photocatalytic degradation phenol was used to investigate the activity of Y3+/TiO2 and its effect on the reaction process. The XRD results show that TiO2 and doped TiO2 are the mixture of anatase and rutile, and the ratio of anatase to rutile was 3:1; doping can retard the development of grain size of TiO2 and decrease the diameter of TiO2 to about 10nm. DRS are used to investigate the ability of absorbing light and the shift of spectrums of TiO2 and doped TiO2. The results show doping makes the light absorption increase and the spectrums of 1.5Y3+/TiO2 and 3.0Y3+/TiO2 both show red shift. The results of experiment of photocatalytic degradation of phenol show that the optimum doping content is wt(Y3+)=1.5%, and the photocatalytic degradation ratio of phenol increases by about 20% compared with the undoped TiO2.
24 Investigation of Characteristics on PdY8.5Ru0.19 Alloy Absorbing-Desorbing Hydrogen and Deuterium
2005, 34(7):1098-1101.
Abstract:
在25℃～100℃的温度范围内,测定了PdY8.5Ru0.19合金吸放氢、氘的P-C-T曲线.与纯钯相比,合金的P-C-T曲线坪区变窄,坪压降低,有显著的同位素效应,但迟滞效应较小.合金吸放氢氘的P-C-T曲线可拟合成p=A(er/B-1)形式.吸氘热焓为-13.9 kJ/mol·D2,熵变为-9.4 J/mol K·D2.进行了25℃下合金吸氢、氘速率的测量,合金吸氢、氘速率常数分别为KH=2.39×10-4 mol·s-1,KD=1.16×10-4 mol·s-1.而且合金的氢化过程用渐进转化模型描述.
在25℃～100℃的温度范围内,测定了PdY8.5Ru0.19合金吸放氢、氘的P-C-T曲线.与纯钯相比,合金的P-C-T曲线坪区变窄,坪压降低,有显著的同位素效应,但迟滞效应较小.合金吸放氢氘的P-C-T曲线可拟合成p=A(er/B-1)形式.吸氘热焓为-13.9 kJ/mol·D2,熵变为-9.4 J/mol K·D2.进行了25℃下合金吸氢、氘速率的测量,合金吸氢、氘速率常数分别为KH=2.39×10-4 mol·s-1,KD=1.16×10-4 mol·s-1.而且合金的氢化过程用渐进转化模型描述.
2005, 34(7):1102-1105.
Abstract:
Zr-based metallic-glass matrix composites, which were reinforced by continuous tungsten fibers, were prepared by melinfiltration casting. The interface reaction and diffusion were analyzed by using X-Ray diffraction, SEM and EPMA. The influence of Nbcontent of the matrix alloy on the interface reaction and diffusion was also investigated. The results illustrate that for the Zr55Al10Ni5Cu3matrix composites an interface eutectoid reaction between W fiber and Zr in the liquid phase takes place and a W5Zr3 phase is formed athe interface. The interface moves to the direction of the liquid phase. For the matrix alloy containing Nb, the addition of Nb in the liquidcauses a significant change of interface reaction. Nb in the liquid phase exhibits a preferential adsorption at the surface of the W fiber, thusreduces the adsorption of Zr atom in the liquid phase at the surface of the W fiber. The activity of absorbed Zr at interface is decreasedand depresses the interface eutectoid reaction between W fiber and liquid. In this case the interface is a simple diffusion layer only. At thesame time the diffusion coefficient of Zr in the W is decreased by Nb addition and the interface moves to the direction of W fiber.
Zr-based metallic-glass matrix composites, which were reinforced by continuous tungsten fibers, were prepared by melinfiltration casting. The interface reaction and diffusion were analyzed by using X-Ray diffraction, SEM and EPMA. The influence of Nbcontent of the matrix alloy on the interface reaction and diffusion was also investigated. The results illustrate that for the Zr55Al10Ni5Cu3matrix composites an interface eutectoid reaction between W fiber and Zr in the liquid phase takes place and a W5Zr3 phase is formed athe interface. The interface moves to the direction of the liquid phase. For the matrix alloy containing Nb, the addition of Nb in the liquidcauses a significant change of interface reaction. Nb in the liquid phase exhibits a preferential adsorption at the surface of the W fiber, thusreduces the adsorption of Zr atom in the liquid phase at the surface of the W fiber. The activity of absorbed Zr at interface is decreasedand depresses the interface eutectoid reaction between W fiber and liquid. In this case the interface is a simple diffusion layer only. At thesame time the diffusion coefficient of Zr in the W is decreased by Nb addition and the interface moves to the direction of W fiber.
2005, 34(7):1106-1108.
Abstract:
To study SiC and other material joining, the wettability of Cu-Al-Si-Ti brazing alloys on silicon carbide was investigated by sessile drop method. It was found that the Ti content and the wetting temperature affected greatly the contact angle. The interface of brazing alloys/silicon carbide was observed and analysed by SEM and XRD. The result indicated that the interface consisted of two layers, e.g. one of them was a thin interface layer with TiC, the other was a thick interface transition layer with Cu-more content and Ti-less content. The diffusion of element Cu determines the property of transition layer. This kind of brazing alloy is a good candidate for the high temperature brazing silicon carbide.
To study SiC and other material joining, the wettability of Cu-Al-Si-Ti brazing alloys on silicon carbide was investigated by sessile drop method. It was found that the Ti content and the wetting temperature affected greatly the contact angle. The interface of brazing alloys/silicon carbide was observed and analysed by SEM and XRD. The result indicated that the interface consisted of two layers, e.g. one of them was a thin interface layer with TiC, the other was a thick interface transition layer with Cu-more content and Ti-less content. The diffusion of element Cu determines the property of transition layer. This kind of brazing alloy is a good candidate for the high temperature brazing silicon carbide.
2005, 34(7):1109-1113.
Abstract:
研究了PLZT铁电陶瓷的电疲劳特性。结果表明：在加上极化电场以后，相对于未疲劳试样，电疲劳试样中沿着电场方向翻转的电畴较少，沿偏离电场方向的电畴较多。SEM分析表明疲劳前样品的断裂模式主要为穿晶断裂，而疲劳后主要为沿晶断裂。利用原位XRD分析得出样品在交流电场下由90。畴变导致的畴变应变高达0．1％，这种反复高畴变应变造成的沿晶微裂纹是造成疲劳试样电畴沿电场方向翻转减少的主要原因，并最终导致了铁电陶瓷的电疲劳。
研究了PLZT铁电陶瓷的电疲劳特性。结果表明：在加上极化电场以后，相对于未疲劳试样，电疲劳试样中沿着电场方向翻转的电畴较少，沿偏离电场方向的电畴较多。SEM分析表明疲劳前样品的断裂模式主要为穿晶断裂，而疲劳后主要为沿晶断裂。利用原位XRD分析得出样品在交流电场下由90。畴变导致的畴变应变高达0．1％，这种反复高畴变应变造成的沿晶微裂纹是造成疲劳试样电畴沿电场方向翻转减少的主要原因，并最终导致了铁电陶瓷的电疲劳。
2005, 34(7):1114-1118.
Abstract:
The feasibility of reduced-friction coating against U-Nb alloy made by plasma spray technique was investigated. Sn soft coating, Sn/ ZrO2 dual coating, Sn and ZrO2 mixing coating and ZrO2 hard coating were prepared by plasma spray technique. The sliding friction behavior of these coatings against U-Nb alloy was evaluated. The friction characteristic of Sn coating is similar to Sn/ ZrO2 dual coating and its friction coefficient is the lowest among the four coatings. Friction coefficient of ZrO2 coating, into which Sn was added, is decreased little, while friction coefficient of ZrO2 hard coating is stabilized at high value with the increase of sliding number of cycles. ZrO2 coating by plasma spray technique plays no role in reducing friction against U-Nb alloy. Plough is the main friction mechanism of these coatings.
The feasibility of reduced-friction coating against U-Nb alloy made by plasma spray technique was investigated. Sn soft coating, Sn/ ZrO2 dual coating, Sn and ZrO2 mixing coating and ZrO2 hard coating were prepared by plasma spray technique. The sliding friction behavior of these coatings against U-Nb alloy was evaluated. The friction characteristic of Sn coating is similar to Sn/ ZrO2 dual coating and its friction coefficient is the lowest among the four coatings. Friction coefficient of ZrO2 coating, into which Sn was added, is decreased little, while friction coefficient of ZrO2 hard coating is stabilized at high value with the increase of sliding number of cycles. ZrO2 coating by plasma spray technique plays no role in reducing friction against U-Nb alloy. Plough is the main friction mechanism of these coatings.
2005, 34(7):1119-1122.
Abstract:
研究了钛合金粉末的温压成形行为。结果发现，在同一压制压力下，钛合金粉末的生坯密度均在140℃左右达到最大值，高于或低于这一温度，生坯密度反而降低。在压制压力为500MPa下，温压成形的脱模力比室温成形的脱模力降低27．7％。同时，温压成形较室温成形改善了钛合金件的显微组织。
研究了钛合金粉末的温压成形行为。结果发现，在同一压制压力下，钛合金粉末的生坯密度均在140℃左右达到最大值，高于或低于这一温度，生坯密度反而降低。在压制压力为500MPa下，温压成形的脱模力比室温成形的脱模力降低27．7％。同时，温压成形较室温成形改善了钛合金件的显微组织。
2005, 34(7):1123-1127.
Abstract:
研究了在1260℃烧结时,烧结时间对Ti-6Al-4V烧结坯力学性能的影响.结果表明平均晶粒尺寸为45 μm的氢化-脱氢粉末样品在1 260C烧结3 h～6 h,其相对密度为95.6%～96.7%、拉伸强度648 MPa～686 MPa、屈服强度526 MPa～615 MPa,但延伸率仅小于4%.90%气雾化(晶粒尺寸为32.5 μm)和10%氢化-脱氢混合粉末样品在1 260℃烧结2 h～6 h,其相对密度大于95%、拉伸强度800 MPa～848 MPa、屈服强度712 MPa～762 MPa、延伸率7.4%～9.5%.混合粉末样品的力学性能几乎达到美国ASTM粉末冶金的标准.
研究了在1260℃烧结时,烧结时间对Ti-6Al-4V烧结坯力学性能的影响.结果表明平均晶粒尺寸为45 μm的氢化-脱氢粉末样品在1 260C烧结3 h～6 h,其相对密度为95.6%～96.7%、拉伸强度648 MPa～686 MPa、屈服强度526 MPa～615 MPa,但延伸率仅小于4%.90%气雾化(晶粒尺寸为32.5 μm)和10%氢化-脱氢混合粉末样品在1 260℃烧结2 h～6 h,其相对密度大于95%、拉伸强度800 MPa～848 MPa、屈服强度712 MPa～762 MPa、延伸率7.4%～9.5%.混合粉末样品的力学性能几乎达到美国ASTM粉末冶金的标准.
2005, 34(7):1128-1130.
Abstract:
利用自行丌发的Gasar装置，成功制备了具有规则气孔分布的藕状多孔金属Mg，并研究了铸型预热温度和气体压力等工艺参数对气孔率、气孔大小和分布的影响。结果表明：提高铸型的预热温度可以完全消除铸锭侧向的无气孔金属壳：随着氢气压力的增大，铸锭的气孔率和气孔平均直径都在减小、气孔的尺寸分布均匀性提高。
利用自行丌发的Gasar装置，成功制备了具有规则气孔分布的藕状多孔金属Mg，并研究了铸型预热温度和气体压力等工艺参数对气孔率、气孔大小和分布的影响。结果表明：提高铸型的预热温度可以完全消除铸锭侧向的无气孔金属壳：随着氢气压力的增大，铸锭的气孔率和气孔平均直径都在减小、气孔的尺寸分布均匀性提高。
2005, 34(7):1131-1134.
Abstract:
Specimens of MB15 magnesium alloy reinforced with SiC whiskers (SiCw/MB15) were fabricated using powder metallurgy route (PM). The influence of SiCw on the 150oC aging behavior of MB15 alloy was investigated by microhardness-testing, and SEM, TEM and tensile tests studied the influence of powder-mixing methods on the distribution of SiCw and the mechanical properties of SiCw/MB15. The results reveal that the double peaks exist in the age-hardening curves of both the unreinforced and the reinforced MB15 alloy, and the addition of SiCw can accelerate the age-hardening process of MB15 alloy apart from increasing its micro- hardness, moreover, the mechanical properties of SiCw/MB15 composite are significantly influenced by powder-mixing methods of PM.
Specimens of MB15 magnesium alloy reinforced with SiC whiskers (SiCw/MB15) were fabricated using powder metallurgy route (PM). The influence of SiCw on the 150oC aging behavior of MB15 alloy was investigated by microhardness-testing, and SEM, TEM and tensile tests studied the influence of powder-mixing methods on the distribution of SiCw and the mechanical properties of SiCw/MB15. The results reveal that the double peaks exist in the age-hardening curves of both the unreinforced and the reinforced MB15 alloy, and the addition of SiCw can accelerate the age-hardening process of MB15 alloy apart from increasing its micro- hardness, moreover, the mechanical properties of SiCw/MB15 composite are significantly influenced by powder-mixing methods of PM.
2005, 34(7):1135-1138.
Abstract:
以喷雾干燥法制备的（W，Ni，Fe)复合氧化物粉末为原料，采用700℃，保温90min的条件进行还原；研究了不同稀土Y含量对还原制备纳粹级W-Ni-Fe复合粉末性能的影响；采用XRD及高倍SEM分别对所制备的复合粉末进行了物相分析、晶粒尺寸测试和形貌观察；并对的制得复合粉末的Fsss粒度、比表面进行了测定与分析。结果表明：不加稀土Y时还原粉末由W和7-（Ni，Fe)两相组成，添加一定量稀土Y的还原粉末有W，7-（Ni，Fe)和Y（Ni0.75W0.25)O3三相组成；当Y的质量分数在0%-0.8%范围内（占90W-Ni-3Fe复合粉末的质量分数），随着Y含量的增高，粉末dBET粒度由96.6nm降到45.2nm，粉末Fsss粒度由0.64μm降到0.28μm，粉末晶粒尺寸由26.1nm降到19.8nm；未添加稀土Y时粉末颗粒为球形，添加一定量的稀土Y，粉末颗粒变为近球形或多面体；添加一定量的稀土Y不仅可以有效地掏晶粒的长大，还可以在一定程度上提高粉末的分散性。
以喷雾干燥法制备的（W，Ni，Fe)复合氧化物粉末为原料，采用700℃，保温90min的条件进行还原；研究了不同稀土Y含量对还原制备纳粹级W-Ni-Fe复合粉末性能的影响；采用XRD及高倍SEM分别对所制备的复合粉末进行了物相分析、晶粒尺寸测试和形貌观察；并对的制得复合粉末的Fsss粒度、比表面进行了测定与分析。结果表明：不加稀土Y时还原粉末由W和7-（Ni，Fe)两相组成，添加一定量稀土Y的还原粉末有W，7-（Ni，Fe)和Y（Ni0.75W0.25)O3三相组成；当Y的质量分数在0%-0.8%范围内（占90W-Ni-3Fe复合粉末的质量分数），随着Y含量的增高，粉末dBET粒度由96.6nm降到45.2nm，粉末Fsss粒度由0.64μm降到0.28μm，粉末晶粒尺寸由26.1nm降到19.8nm；未添加稀土Y时粉末颗粒为球形，添加一定量的稀土Y，粉末颗粒变为近球形或多面体；添加一定量的稀土Y不仅可以有效地掏晶粒的长大，还可以在一定程度上提高粉末的分散性。
2005, 34(7):1139-1143.
Abstract:
80.7W-13.2Ni-6.1Fe(atom percent)tungsten heavy alloys were prepared by mechanical alloying (MA). The volume fraction of the remanent crystalline W in the as-milled materials and the W atom percent in amorphous phase were measured using a method similar to the internal standard method and the route of amorphization. The mechanism of the amorphous phase forming in the process of milling was analyzed. The results show that the crystalline size of tungsten reaches 11 nm~20 nm after milling for 60 h. Ni dissolves in crystalline W and then amorphization of W supersaturated solid solution occurs after milling for 20 h. Forming of the supersaturated solid solution is attributed to dissolving of the small particles with large stored energy into W continuously and the critical size of the Ni particles which can dissolve in the W is 3nm calculated based on the stored energy model. During milling, the volume fraction of the remanent crystalling W is decreased, and the W contents in the amorphous phase remain content, approximately 63W-37Ni(Fe), due to the Fe contamination dissolving into W continuously.
80.7W-13.2Ni-6.1Fe(atom percent)tungsten heavy alloys were prepared by mechanical alloying (MA). The volume fraction of the remanent crystalline W in the as-milled materials and the W atom percent in amorphous phase were measured using a method similar to the internal standard method and the route of amorphization. The mechanism of the amorphous phase forming in the process of milling was analyzed. The results show that the crystalline size of tungsten reaches 11 nm~20 nm after milling for 60 h. Ni dissolves in crystalline W and then amorphization of W supersaturated solid solution occurs after milling for 20 h. Forming of the supersaturated solid solution is attributed to dissolving of the small particles with large stored energy into W continuously and the critical size of the Ni particles which can dissolve in the W is 3nm calculated based on the stored energy model. During milling, the volume fraction of the remanent crystalling W is decreased, and the W contents in the amorphous phase remain content, approximately 63W-37Ni(Fe), due to the Fe contamination dissolving into W continuously.
2005, 34(7):1144-1146.
Abstract:
采用Nb与Nb2O5固-固反应制备低价铌氧化物粉末,用正交试验法及方差分析对制备低价铌氧化物电解电容器阳极的工艺条件进行了优化。所研制的电容器阳极比容69500μF·V·g-1、损耗11.25%、漏电流(K值)1.8×10-4μA·μF-1·V-1,优于FTa16-300电容器钽粉国家标准(GB/T3136-1995)。
采用Nb与Nb2O5固-固反应制备低价铌氧化物粉末,用正交试验法及方差分析对制备低价铌氧化物电解电容器阳极的工艺条件进行了优化。所研制的电容器阳极比容69500μF·V·g-1、损耗11.25%、漏电流(K值)1.8×10-4μA·μF-1·V-1,优于FTa16-300电容器钽粉国家标准(GB/T3136-1995)。
2005, 34(7):1147-1150.
Abstract:
为了改善空气电极的电催化性能，提高锌空气电池的放电电流密度。采用溶胶．凝胶法制备了锌空气电池用催化剂LiMn2-xCoxO4。通过X射线衍射(XRD)、粒径分布、稳态电流．电压极化曲线等方法，研究了所得催化剂的结构及其电催化性能。并与高温固相反应法所得催化剂的结构与电催化性能作了对比。结果表明，当反应体系的pH值为7～8、温度为80℃时所得凝胶再经600℃下保温处理12h，可以得到具有最高催化活性的催化剂；溶胶．凝胶法合成催化剂的粒径较小，主要集中在1μm～4．5μm的范围内，粒度分布较窄，而高温固相反应法合成催化剂的粒径较大，主要集中在5μm～30μm的范围内。粒度分布较宽：2种方法所得的催化剂具有完全相同的晶态结构；溶胶．凝胶法和高温固相反应法催化剂的空气电极在-0．6V极化电位下的电流密度分别达到250mA／cm^2和210mA／cm^2，前者比后者的较高。
为了改善空气电极的电催化性能，提高锌空气电池的放电电流密度。采用溶胶．凝胶法制备了锌空气电池用催化剂LiMn2-xCoxO4。通过X射线衍射(XRD)、粒径分布、稳态电流．电压极化曲线等方法，研究了所得催化剂的结构及其电催化性能。并与高温固相反应法所得催化剂的结构与电催化性能作了对比。结果表明，当反应体系的pH值为7～8、温度为80℃时所得凝胶再经600℃下保温处理12h，可以得到具有最高催化活性的催化剂；溶胶．凝胶法合成催化剂的粒径较小，主要集中在1μm～4．5μm的范围内，粒度分布较窄，而高温固相反应法合成催化剂的粒径较大，主要集中在5μm～30μm的范围内。粒度分布较宽：2种方法所得的催化剂具有完全相同的晶态结构；溶胶．凝胶法和高温固相反应法催化剂的空气电极在-0．6V极化电位下的电流密度分别达到250mA／cm^2和210mA／cm^2，前者比后者的较高。
2005, 34(7):1151-1153.
Abstract:
利用溶胶-凝胶法在SiO2凝胶体系中制备了纳米级的锶铁氧体磁性微粒，该磁性微粒组成为3O％SrFe12O19和70％SiO2(质量百分含量)。对该微粒进行了XRD分析，利用VSM对样品进行了磁性能研究。研究表明，相对于共沉淀法制备的纯锶铁氧体微粒，在SiO2凝胶体系中制备的SrM微粒仍保持为六方磁铅石型结构，但是粒径明显降低，850℃结样品的粒径约为31nm；且内禀矫顽力Hc有了显著的提高，850℃烧结样品的内禀矫顽力达到518．4kA／m，而比饱和磁化强度则有所下降。并对其磁性能变化的原因进行了分析。
利用溶胶-凝胶法在SiO2凝胶体系中制备了纳米级的锶铁氧体磁性微粒，该磁性微粒组成为3O％SrFe12O19和70％SiO2(质量百分含量)。对该微粒进行了XRD分析，利用VSM对样品进行了磁性能研究。研究表明，相对于共沉淀法制备的纯锶铁氧体微粒，在SiO2凝胶体系中制备的SrM微粒仍保持为六方磁铅石型结构，但是粒径明显降低，850℃结样品的粒径约为31nm；且内禀矫顽力Hc有了显著的提高，850℃烧结样品的内禀矫顽力达到518．4kA／m，而比饱和磁化强度则有所下降。并对其磁性能变化的原因进行了分析。
38 Preparation of SrBi4Ti4O15/Ag Composites Sintered at Low Temperature and Their Dielectric Properties
2005, 34(7):1154-1157.
Abstract:
摘要：采用固相烧结工艺制备了SrBi4Ti4O15(SBTi)／Ag铁电复合材料，通过X射线衍射、光学金相显微镜和扫描电子显微镜对材料的组成和微观结构进行了研究，并测量样品的介电温度谱。结果表明：复合材料是由SBTi和Ag两相组成。微量金属Ag的加入使SBTi铁电陶瓷的烧结温度从1120℃降低到950℃以下：可以适当提高铁电陶瓷从室温到200℃的介电常数，但对材料的介电损耗影响很小。同时Ag的加入压抑了介电温度曲线上的介电常数的Curie峰。
摘要：采用固相烧结工艺制备了SrBi4Ti4O15(SBTi)／Ag铁电复合材料，通过X射线衍射、光学金相显微镜和扫描电子显微镜对材料的组成和微观结构进行了研究，并测量样品的介电温度谱。结果表明：复合材料是由SBTi和Ag两相组成。微量金属Ag的加入使SBTi铁电陶瓷的烧结温度从1120℃降低到950℃以下：可以适当提高铁电陶瓷从室温到200℃的介电常数，但对材料的介电损耗影响很小。同时Ag的加入压抑了介电温度曲线上的介电常数的Curie峰。
2005, 34(7):1158-1161.
Abstract:
Various processes of the Mo/Si thin films deposited on Si (001) substrates by RF magnetron sputtering technique were carefully investigated and the MoSi2 thin film with the single tetragonal phase and low resistivity was successfully prepared. X-ray diffraction, scanning electrical microscopy, atomic force microscope and Four-probe resistance meter were used to determine their structures, surface morphologies and electrical properties. Results show that the electrical property of the Mo/Si films depends strongly upon their microstructure and the phase composition. The as-deposited film mainly belongs to amorphous. After annealing at the high temperature. The great change of the film crystallization structure takes place, and its phase composition varies with the as-deposited processes. The effect of the crystallization enhances obviously, and the square resistance of the film drops greatly.
Various processes of the Mo/Si thin films deposited on Si (001) substrates by RF magnetron sputtering technique were carefully investigated and the MoSi2 thin film with the single tetragonal phase and low resistivity was successfully prepared. X-ray diffraction, scanning electrical microscopy, atomic force microscope and Four-probe resistance meter were used to determine their structures, surface morphologies and electrical properties. Results show that the electrical property of the Mo/Si films depends strongly upon their microstructure and the phase composition. The as-deposited film mainly belongs to amorphous. After annealing at the high temperature. The great change of the film crystallization structure takes place, and its phase composition varies with the as-deposited processes. The effect of the crystallization enhances obviously, and the square resistance of the film drops greatly.
2005, 34(7):1162-1165.
Abstract:
Hexagonal GaN micro-ribbons were synthesized through nitriding Ga2O3 films under flowing ammonia. Ga2O3 films were deposited on the Ga-diffused Si (111) substrates by radio frequency (r.f.) magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED); X-ray photo electronic spectrometer (XPS) and photoluminescence (PL) spectroscopy were used to characterize the structure, surface morphology, composition and optical property of the synthesized samples. SEM images show that GaN micro-ribbons with 100-300rim in diameter are randomly distributed on the uniform films. XRD, XPS and SAED analysis suggest the micro-ribbons are polycrystalline GaN with hexagonal structure and preferentially grow in the [001] direction. The PL spectrum has a remarkable blue shift compared with the reported values of bulk GaN, which might be ascribed to quantum confinement effects.
Hexagonal GaN micro-ribbons were synthesized through nitriding Ga2O3 films under flowing ammonia. Ga2O3 films were deposited on the Ga-diffused Si (111) substrates by radio frequency (r.f.) magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED); X-ray photo electronic spectrometer (XPS) and photoluminescence (PL) spectroscopy were used to characterize the structure, surface morphology, composition and optical property of the synthesized samples. SEM images show that GaN micro-ribbons with 100-300rim in diameter are randomly distributed on the uniform films. XRD, XPS and SAED analysis suggest the micro-ribbons are polycrystalline GaN with hexagonal structure and preferentially grow in the [001] direction. The PL spectrum has a remarkable blue shift compared with the reported values of bulk GaN, which might be ascribed to quantum confinement effects.
41 Influence of Vacuum Annealing on Properties of ZnO:Ga Films Prepared by r.f. Magnetron Sputtering
2005, 34(7):1166-1168.
Abstract:
采用射频磁控溅射法在玻璃衬底上低温制备出了镓掺杂氧化锌(ZnO:Ga)透明导电膜,研究了真空退火对薄膜结构、电学和光学特性的影响。结果表明:真空退火后,薄膜结构得到明显改善,电阻率由退火前的1.13×10-3?·cm下降到5.4×10-4?·cm,在可见光区的平均透过率也由未退火前的83%提高到退火后的90%以上。
采用射频磁控溅射法在玻璃衬底上低温制备出了镓掺杂氧化锌(ZnO:Ga)透明导电膜,研究了真空退火对薄膜结构、电学和光学特性的影响。结果表明:真空退火后,薄膜结构得到明显改善,电阻率由退火前的1.13×10-3?·cm下降到5.4×10-4?·cm,在可见光区的平均透过率也由未退火前的83%提高到退火后的90%以上。
2005, 34(7):1169-1172.
Abstract:
以锡盐和金属铟为原料采用胶体法制备ITO前驱物浆料，通过提拉法在镀有SiO2薄层的浮法玻璃基片上制备透明导电ITO薄膜。用TEM测定ITO前驱物浆料颗粒大小；用XRD、SEM、AES分别对ITO薄膜的结构和表面形貌进行表征；用分光光度计和四探针电阻仪检测ITO薄膜光电性能。结果表明：ITO前驱物浆料的颗粒粒径为2nm～15nm，具有较好的分散性和稳定性：ITO薄膜厚度越大，方电阻越小，平均透过率下降；ITO薄膜在波长为360nm～800nm区的透过率随膜厚增加有不同的影响；退火温度越高，膜方电阻越低；当膜厚为300nm、退火温度600℃时，膜方电阻达到2581Ω／n，其透过率在波长550nm处达到89．6％，且薄膜表面平整。
以锡盐和金属铟为原料采用胶体法制备ITO前驱物浆料，通过提拉法在镀有SiO2薄层的浮法玻璃基片上制备透明导电ITO薄膜。用TEM测定ITO前驱物浆料颗粒大小；用XRD、SEM、AES分别对ITO薄膜的结构和表面形貌进行表征；用分光光度计和四探针电阻仪检测ITO薄膜光电性能。结果表明：ITO前驱物浆料的颗粒粒径为2nm～15nm，具有较好的分散性和稳定性：ITO薄膜厚度越大，方电阻越小，平均透过率下降；ITO薄膜在波长为360nm～800nm区的透过率随膜厚增加有不同的影响；退火温度越高，膜方电阻越低；当膜厚为300nm、退火温度600℃时，膜方电阻达到2581Ω／n，其透过率在波长550nm处达到89．6％，且薄膜表面平整。
2005, 34(7):1173-1176.
Abstract:
制备了一种新的Er^3 ／Tm^3 /Yb^3 共掺氧卤碲酸盐玻璃。研究了基质玻璃的热稳定性能、Raman光谱和上转换发光。发现：氧卤碲酸盐玻璃具有好的热稳定性能和低的声子能量，在980nmLD激发下，可同时观察到明显的蓝色(476nm)、绿色(530nm和545nm)和红色(656nm)上转换发光。上转换蓝光(476nm)是由于Tm^3 离子1^G4→3^3H6跃迁，上转换的绿光(530nm和545nm)是由于Er^3 离子2^H11/2→4^I15／2和4^S3/2→4^I15/2跃迁，上转换红光(656nm)是由于Er^3 离子4^F9/2→4I15/2跃迁。
制备了一种新的Er^3 ／Tm^3 /Yb^3 共掺氧卤碲酸盐玻璃。研究了基质玻璃的热稳定性能、Raman光谱和上转换发光。发现：氧卤碲酸盐玻璃具有好的热稳定性能和低的声子能量，在980nmLD激发下，可同时观察到明显的蓝色(476nm)、绿色(530nm和545nm)和红色(656nm)上转换发光。上转换蓝光(476nm)是由于Tm^3 离子1^G4→3^3H6跃迁，上转换的绿光(530nm和545nm)是由于Er^3 离子2^H11/2→4^I15／2和4^S3/2→4^I15/2跃迁，上转换红光(656nm)是由于Er^3 离子4^F9/2→4I15/2跃迁。
