Volume 34,Issue 12,2005 Table of Contents
2005, 34(12):1849-1853.
Abstract:
In recent years, growth of GaN-based materials-related quantum dots has become a hot topic in semiconductor materials research. Considerable efforts have been devoted to growth of self-assembled quantum dots of GaN-based materials via MOCVD (Metal Organic Chemical Vapor Deposition) and there are a lot of relevant literatures. There is, however, few review papers for the topic. In this paper, different experimental methods for fabrication of quantum dots of GaN-based materials via MOCVD are critically reviewed and the experimental conditions and parameters, which may affect growth of the quantum dots, are analyzed, with an aim at providing some critical reference for the related future experiment research.
In recent years, growth of GaN-based materials-related quantum dots has become a hot topic in semiconductor materials research. Considerable efforts have been devoted to growth of self-assembled quantum dots of GaN-based materials via MOCVD (Metal Organic Chemical Vapor Deposition) and there are a lot of relevant literatures. There is, however, few review papers for the topic. In this paper, different experimental methods for fabrication of quantum dots of GaN-based materials via MOCVD are critically reviewed and the experimental conditions and parameters, which may affect growth of the quantum dots, are analyzed, with an aim at providing some critical reference for the related future experiment research.
2005, 34(12):1854-1856.
Abstract:
采用PLD法在LaAlO3（012）单晶衬底上外延生长了高、双掺杂La1/3（Ca2，3Sr1/3）2，3MnO3（LCSMO）薄膜。薄膜的x射线衍射谱表明，薄膜具有铫钛矿赝立方结构，且具有（012）方向的择优取向：用原子力显微镜对薄膜的表面形貌进行了分析，发现薄膜表面相对比较平坦；在密封的液氮杜瓦瓶里用四探针法对薄膜的输运特性进行了测试，电阻一温度试验曲线表明，在温度77K～400K的范围内薄膜呈现类半导体特性，没有金属一绝缘体转变温度（TM1）出现；薄膜的红外透射谱在606cm。处宵一个很强的吸收峰，由红外透射谱计算出光学能隙氏。。大约为0．7eV，薄膜的光学折射率为1．373。分析认为LCSMO薄膜的类半导体特性是由于A离子半径变化引起晶格畸变造成的。
采用PLD法在LaAlO3（012）单晶衬底上外延生长了高、双掺杂La1/3（Ca2，3Sr1/3）2，3MnO3（LCSMO）薄膜。薄膜的x射线衍射谱表明，薄膜具有铫钛矿赝立方结构，且具有（012）方向的择优取向：用原子力显微镜对薄膜的表面形貌进行了分析，发现薄膜表面相对比较平坦；在密封的液氮杜瓦瓶里用四探针法对薄膜的输运特性进行了测试，电阻一温度试验曲线表明，在温度77K～400K的范围内薄膜呈现类半导体特性，没有金属一绝缘体转变温度（TM1）出现；薄膜的红外透射谱在606cm。处宵一个很强的吸收峰，由红外透射谱计算出光学能隙氏。。大约为0．7eV，薄膜的光学折射率为1．373。分析认为LCSMO薄膜的类半导体特性是由于A离子半径变化引起晶格畸变造成的。
2005, 34(12):1857-1861.
Abstract:
研究了用简单混杂和球磨方法制备的天然石墨／锑复合材料作为锂离子电池负极材料的嵌／放锂性能以及循环过程中嵌／放锂容量衰减机理。复合材料中的锑以独立的可逆嵌／放锂反应参与吸／放锂过程并显著提高复合材料的嵌／放锂容量。较大颗粒的锑在嵌／放锂过程中体积剧变导致颗粒破碎、电接触恶化而渐渐失去嵌／放锂活性，因此由简单混杂所获得石墨／锑复合材料在循环过程中容量逐渐降低；采用球磨方法在天然石墨颗粒表面形成弥散分布的小颗粒锑则能获得具有较高可逆容量和较好的循环稳定性的石墨／锑复合锂离子电池负极材料。
研究了用简单混杂和球磨方法制备的天然石墨／锑复合材料作为锂离子电池负极材料的嵌／放锂性能以及循环过程中嵌／放锂容量衰减机理。复合材料中的锑以独立的可逆嵌／放锂反应参与吸／放锂过程并显著提高复合材料的嵌／放锂容量。较大颗粒的锑在嵌／放锂过程中体积剧变导致颗粒破碎、电接触恶化而渐渐失去嵌／放锂活性，因此由简单混杂所获得石墨／锑复合材料在循环过程中容量逐渐降低；采用球磨方法在天然石墨颗粒表面形成弥散分布的小颗粒锑则能获得具有较高可逆容量和较好的循环稳定性的石墨／锑复合锂离子电池负极材料。
2005, 34(12):1862-1865.
Abstract:
以LiOH·H2O,Ni2O3,Co2O3和Al(OH)3为原料,采用固相反应法合成Co-Al共掺入LiNiO2的化合物LiNi0.85Co0.10Al0.05O2,由TG-DTA,XRD,SEM,DSC和电化学测试表征材料.结果表明,该材料首次放电容量达186.2mAh/g(3.0 V～4.3 V,18 mA/g),10次循环之后,容量还有180.1 mAh/g,容量保持率为96.7%;与未掺杂的LiNiO2相比,该材料显示出良好的循环性能,且热稳定性也有所提高,是一种很有应用前景的锂离子电池正极材料.
以LiOH·H2O,Ni2O3,Co2O3和Al(OH)3为原料,采用固相反应法合成Co-Al共掺入LiNiO2的化合物LiNi0.85Co0.10Al0.05O2,由TG-DTA,XRD,SEM,DSC和电化学测试表征材料.结果表明,该材料首次放电容量达186.2mAh/g(3.0 V～4.3 V,18 mA/g),10次循环之后,容量还有180.1 mAh/g,容量保持率为96.7%;与未掺杂的LiNiO2相比,该材料显示出良好的循环性能,且热稳定性也有所提高,是一种很有应用前景的锂离子电池正极材料.
2005, 34(12):1866-1870.
Abstract:
For decreasing the cost of AB_5-type hydrogen storage alloys, a low-cobalt Ml_(0.9)Mg_(0.1)Ni_(3.4)Co_(0.3)Al(0.3) alloy was investigated by examining the alloy structure, phase composition and some properties. Its properties were compared with those of a commercial alloy MmNi_(3.55)Co_(0.75)Mn_(0.4)Al_(0.3). The experiments' outcome shows that the low-cobalt alloy is composed of Mg-free LaNi_5 phase as matrix and Mg-contained LaNi3 phase as secondary phase. The hydrogen storage capacity (1.36wt% and 1.37wt% respectively), the greatest discharge capacity (320 mAh/g and 324 mAh/g respectively) and cycling stability (the residual capacity of two alloys is all 88% ) of Ml_(0.9)Mg_(3.4)Ni_(3.4)Co(0.3)Al_(0.3) are as good as those of MmNi_(3.55)Co(0.75)Mn(0.4)Al_(0.3). However, after the discharge current density exceeds 300 mA/g, the high-rate discharge abilities (HRD) of Ml_(0.9)Mg_(0.1)Ni_(3.4)Co_(0.3)Al_(0.3) are apparently better than those of MmNi_(3.55)Co_(0.75)Mn_(0.4)Al_(0.3).It is because there exists Mg-contained LaNi_3 phase as secondary phase which improves the electrochemical catalytic activity of alloy particles surface and the structure toughness of alloy particles.
For decreasing the cost of AB_5-type hydrogen storage alloys, a low-cobalt Ml_(0.9)Mg_(0.1)Ni_(3.4)Co_(0.3)Al(0.3) alloy was investigated by examining the alloy structure, phase composition and some properties. Its properties were compared with those of a commercial alloy MmNi_(3.55)Co_(0.75)Mn_(0.4)Al_(0.3). The experiments' outcome shows that the low-cobalt alloy is composed of Mg-free LaNi_5 phase as matrix and Mg-contained LaNi3 phase as secondary phase. The hydrogen storage capacity (1.36wt% and 1.37wt% respectively), the greatest discharge capacity (320 mAh/g and 324 mAh/g respectively) and cycling stability (the residual capacity of two alloys is all 88% ) of Ml_(0.9)Mg_(3.4)Ni_(3.4)Co(0.3)Al_(0.3) are as good as those of MmNi_(3.55)Co(0.75)Mn(0.4)Al_(0.3). However, after the discharge current density exceeds 300 mA/g, the high-rate discharge abilities (HRD) of Ml_(0.9)Mg_(0.1)Ni_(3.4)Co_(0.3)Al_(0.3) are apparently better than those of MmNi_(3.55)Co_(0.75)Mn_(0.4)Al_(0.3).It is because there exists Mg-contained LaNi_3 phase as secondary phase which improves the electrochemical catalytic activity of alloy particles surface and the structure toughness of alloy particles.
2005, 34(12):1875-1878.
Abstract:
Fe89Zr7B4薄带在550℃～720℃的温度范围内分别退火20min，析出晶粒为13nm～17nm的α-Fe。720℃退火时有微量的第二相析出。Fe89Zr7B4纳米晶薄带的巨磁阻抗效应与退火温度紧密相关，存在一个最佳退火温度，约为650℃。进一步的实验结果显示：Fe89Zr7B4纳米晶薄带在直流磁场引导下横向磁导率的变化率在650℃存在最大值。经典电磁理论与磁谱结合的模型能较好地描述Fe89Zr7B4纳米晶薄带磁阻抗与频率的依赖关系。实验数据和理论计算结果均表明，巨磁阻抗效应与磁场引导的横向磁导率的变化紧密相关。
Fe89Zr7B4薄带在550℃～720℃的温度范围内分别退火20min，析出晶粒为13nm～17nm的α-Fe。720℃退火时有微量的第二相析出。Fe89Zr7B4纳米晶薄带的巨磁阻抗效应与退火温度紧密相关，存在一个最佳退火温度，约为650℃。进一步的实验结果显示：Fe89Zr7B4纳米晶薄带在直流磁场引导下横向磁导率的变化率在650℃存在最大值。经典电磁理论与磁谱结合的模型能较好地描述Fe89Zr7B4纳米晶薄带磁阻抗与频率的依赖关系。实验数据和理论计算结果均表明，巨磁阻抗效应与磁场引导的横向磁导率的变化紧密相关。
7 Microstructure Comparison between Co-Sputtered and Multilayer-Sputtered FePt:Ag Granular Thin Films
2005, 34(12):1879-1881.
Abstract:
Two different sputtering modes, co-sputtering and multilayer-sputtering, were used to fabricate FePt:Ag granular thin films. It is observed by the MFM and TEM images that smaller magnetic domain patterns and grains are more uniformly distributed in the co-sputtered granular films compared to in multilayer-sputtered ones. This difference in the microstructure is explained to be attributed to the more randomly distributed Ag atoms in the co-sputtered films. Further study on in-depth defects in these films confirms this explanation.
Two different sputtering modes, co-sputtering and multilayer-sputtering, were used to fabricate FePt:Ag granular thin films. It is observed by the MFM and TEM images that smaller magnetic domain patterns and grains are more uniformly distributed in the co-sputtered granular films compared to in multilayer-sputtered ones. This difference in the microstructure is explained to be attributed to the more randomly distributed Ag atoms in the co-sputtered films. Further study on in-depth defects in these films confirms this explanation.
2005, 34(12):1882-1885.
Abstract:
采用磁控溅射方法在1Cr18Ni9Ti不锈钢基体上沉积Ti-Si-N纳米薄膜。结果发现：随着Si含量增加，薄膜的晶粒尺寸逐渐变小，晶粒尺寸范围在3nm～20nm之间。薄膜的显微硬度相对于TiN有明显增加，最大硬度可达43．5GPa。Si元素的加入亦改善了膜基结合强度。同时发现，Ti-Si-N纳米薄膜的摩擦系数和比磨损率随着Si含量的增加先减小后增加，其高温摩擦系数明显低干常温，但比磨损率却有显著提高。
采用磁控溅射方法在1Cr18Ni9Ti不锈钢基体上沉积Ti-Si-N纳米薄膜。结果发现：随着Si含量增加，薄膜的晶粒尺寸逐渐变小，晶粒尺寸范围在3nm～20nm之间。薄膜的显微硬度相对于TiN有明显增加，最大硬度可达43．5GPa。Si元素的加入亦改善了膜基结合强度。同时发现，Ti-Si-N纳米薄膜的摩擦系数和比磨损率随着Si含量的增加先减小后增加，其高温摩擦系数明显低干常温，但比磨损率却有显著提高。
2005, 34(12):1886-1889.
Abstract:
采用GNP（Glycine-Nitrate Process）法合成La0.8Ca0.2CrO3初级粉料，研究甘氨酸用量对产物的晶体结构和显微形貌的影响，并测试烧结体的相对密度和电导率。研究结果表明，甘氨酸与金属离子的摩尔比（G／M^n＋）控制在2．0～2．5时可得到颗粒尺寸细小、均匀（100nm～200nm）的单相钙钛矿粉体，烧结温度为1350℃时样品的相对密度达到91．0％，测试温度为800℃时样品的电导率达到30．5S.cm^-1。与常规固相法相比，GNP法制备的样品具有更好的烧结活性和导电性能。
采用GNP（Glycine-Nitrate Process）法合成La0.8Ca0.2CrO3初级粉料，研究甘氨酸用量对产物的晶体结构和显微形貌的影响，并测试烧结体的相对密度和电导率。研究结果表明，甘氨酸与金属离子的摩尔比（G／M^n＋）控制在2．0～2．5时可得到颗粒尺寸细小、均匀（100nm～200nm）的单相钙钛矿粉体，烧结温度为1350℃时样品的相对密度达到91．0％，测试温度为800℃时样品的电导率达到30．5S.cm^-1。与常规固相法相比，GNP法制备的样品具有更好的烧结活性和导电性能。
2005, 34(12):1890-1893.
Abstract:
采用热氧化方法在TiNi合金表面制备了TiO2薄膜，并考察了TiO2／TiNi电极在KOH溶液中的光电化学性能。结果表明，TiNi贮氢合金表面形成的TiO2薄膜为金红石型，结晶度随氧化温度升高逐渐增大；TiO2薄膜结构、光电流和界面阻抗之间存在良好的相关性，700℃制备的TiO2薄膜光响应电流最大，电极阻抗谱与镍氢电池体系合金负极阻抗特征相似，高频区半圆对应于吸附氢的形成，而低频区Warburg线性关系则反映了氢在电极中的固态扩散过程；在光照射下具有特殊的光充电贮氢性能，放电容量从暗态时的5mAh／g提高至光照时的15mAh／g，对光充电反应机理作了初步分析。
采用热氧化方法在TiNi合金表面制备了TiO2薄膜，并考察了TiO2／TiNi电极在KOH溶液中的光电化学性能。结果表明，TiNi贮氢合金表面形成的TiO2薄膜为金红石型，结晶度随氧化温度升高逐渐增大；TiO2薄膜结构、光电流和界面阻抗之间存在良好的相关性，700℃制备的TiO2薄膜光响应电流最大，电极阻抗谱与镍氢电池体系合金负极阻抗特征相似，高频区半圆对应于吸附氢的形成，而低频区Warburg线性关系则反映了氢在电极中的固态扩散过程；在光照射下具有特殊的光充电贮氢性能，放电容量从暗态时的5mAh／g提高至光照时的15mAh／g，对光充电反应机理作了初步分析。
2005, 34(12):1894-1896.
Abstract:
采用机械力化学法制备厂纳米Y2O3：Eu^3＋粉体。利用TG-DSC，XRD，TEM等实验技术对其进行了表征，并对其光谱特性进行r研究。结果表明：所得纳米Y2O3：Eu^3＋为球形，粒度分布均匀，粒径为约30nm～50nm，与体材料相比，该纳米品的发射光普发生蓝移，激发光谱发生红移。
采用机械力化学法制备厂纳米Y2O3：Eu^3＋粉体。利用TG-DSC，XRD，TEM等实验技术对其进行了表征，并对其光谱特性进行r研究。结果表明：所得纳米Y2O3：Eu^3＋为球形，粒度分布均匀，粒径为约30nm～50nm，与体材料相比，该纳米品的发射光普发生蓝移，激发光谱发生红移。
2005, 34(12):1897-1900.
Abstract:
Oxide ceramic layer was obtained on Ti-6Al-4V alloy in NaAlO_2, Na_3PO_4 mixed solution by micro-arc oxidation (MAO) technique. The structure and composition of MAO coatings were analyzed by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The results show: the surface and interface have the porous structure, but the difference between the diameter of pores in surface is quite large, the difference in interface is quite small, and there are some long hill paralleled to each other in interface. There is no obvious boundary between the loose layer and dense layer. The interface between the substrate and MAO coatings has a z-zig structure. The surface and interface are composed of Ti, Al, V, P elements, and Al element is inclined to enrich in surface, but P element enriched in interface according to EDS results. TiO_2, Al_2O_3, TiAl_2O_5 phases are identified in surface and interface, and the P element exists in PO_4~(3-) radical according to XPS analysis. V_2O_5 phase can be found in the interface and V element does not exist in the surface according to XPS analysis.
Oxide ceramic layer was obtained on Ti-6Al-4V alloy in NaAlO_2, Na_3PO_4 mixed solution by micro-arc oxidation (MAO) technique. The structure and composition of MAO coatings were analyzed by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The results show: the surface and interface have the porous structure, but the difference between the diameter of pores in surface is quite large, the difference in interface is quite small, and there are some long hill paralleled to each other in interface. There is no obvious boundary between the loose layer and dense layer. The interface between the substrate and MAO coatings has a z-zig structure. The surface and interface are composed of Ti, Al, V, P elements, and Al element is inclined to enrich in surface, but P element enriched in interface according to EDS results. TiO_2, Al_2O_3, TiAl_2O_5 phases are identified in surface and interface, and the P element exists in PO_4~(3-) radical according to XPS analysis. V_2O_5 phase can be found in the interface and V element does not exist in the surface according to XPS analysis.
13 Thermo-Natatorial Phenomena and Influence in Preparing Nano Ni Powder by Plasma Arc Spraying Method
2005, 34(12):1901-1904.
Abstract:
利用等离子体法制备金属纳米镍粉。发现收集系统效率偏低，且平均粒度越小的粉末收得率越低。分析表明，对于纳米粒子不等温流场中的气固两相流输运过程，粒子沉降由重力沉降过渡到热泳沉降；粒子平均粒度从10μm下降到50nm时，热泳力与重力、马格纽斯升力的比值分别从0．07和0．02上升到2820和945，即热泳力因素占主导地位：温度梯度越大，粒子平均粒度越小。则热泳影响越显著，这是影响收得率的决定性因素。
利用等离子体法制备金属纳米镍粉。发现收集系统效率偏低，且平均粒度越小的粉末收得率越低。分析表明，对于纳米粒子不等温流场中的气固两相流输运过程，粒子沉降由重力沉降过渡到热泳沉降；粒子平均粒度从10μm下降到50nm时，热泳力与重力、马格纽斯升力的比值分别从0．07和0．02上升到2820和945，即热泳力因素占主导地位：温度梯度越大，粒子平均粒度越小。则热泳影响越显著，这是影响收得率的决定性因素。
2005, 34(12):1905-1908.
Abstract:
研究了活性填料纳米Ni粉对陶瓷先驱体聚硅氮烷连接反应烧结SiC陶瓷接头性能的影响，同时与惰性填料纳米SiC粉及活性填料微米Ni粉进行了对比，指出填料的种类及颗粒度对连接强度均有较大影响。活性填料纳米Ni粉的加入可减少连接层内的孔隙和裂纹，同时还可以与聚硅氮烷的裂解产物及母材发生反应，促进聚硅氮烷的裂解，从而降低连接温度，提高连接强度。当连接温度为1200℃时，其最大抗弯强度达到251．6MPa。微观研究表明，连接层结构较为均匀致密，且与母材间界面结合良好。惰性填料纳米SiC粉对连接强度没有明显改善。微米Ni粉因不能与先驱体形成均匀的连接层而导致连接强度降低。
研究了活性填料纳米Ni粉对陶瓷先驱体聚硅氮烷连接反应烧结SiC陶瓷接头性能的影响，同时与惰性填料纳米SiC粉及活性填料微米Ni粉进行了对比，指出填料的种类及颗粒度对连接强度均有较大影响。活性填料纳米Ni粉的加入可减少连接层内的孔隙和裂纹，同时还可以与聚硅氮烷的裂解产物及母材发生反应，促进聚硅氮烷的裂解，从而降低连接温度，提高连接强度。当连接温度为1200℃时，其最大抗弯强度达到251．6MPa。微观研究表明，连接层结构较为均匀致密，且与母材间界面结合良好。惰性填料纳米SiC粉对连接强度没有明显改善。微米Ni粉因不能与先驱体形成均匀的连接层而导致连接强度降低。
2005, 34(12):1909-1912.
Abstract:
采用熔体快淬法制备了LaFe11．5Si1．5化合物。利用X射线衍射和能谱分析测定了熔体快淬带的相组成和元素分布：利用磁性能测试结果计算了磁熵变。结果表明：熔体快淬可以得到元素分布均匀的LaFe11．5Si1．5薄带，其相组成为NaZn13型LaFe11．5Si1．5化合物和大量α-Fe。退火后，快淬带中的α-Fe含量大大降低，得到了近似单相的LaFe11．5Si1．5化合物。由磁性能测试并经计算发现，快淬带经1000℃，6h时效后具有巨大的磁熵变。由此可见，熔体快淬可成为一种制备更廉价的高性能磁致制冷材料的新方法。
采用熔体快淬法制备了LaFe11．5Si1．5化合物。利用X射线衍射和能谱分析测定了熔体快淬带的相组成和元素分布：利用磁性能测试结果计算了磁熵变。结果表明：熔体快淬可以得到元素分布均匀的LaFe11．5Si1．5薄带，其相组成为NaZn13型LaFe11．5Si1．5化合物和大量α-Fe。退火后，快淬带中的α-Fe含量大大降低，得到了近似单相的LaFe11．5Si1．5化合物。由磁性能测试并经计算发现，快淬带经1000℃，6h时效后具有巨大的磁熵变。由此可见，熔体快淬可成为一种制备更廉价的高性能磁致制冷材料的新方法。
2005, 34(12):1913-1916.
Abstract:
采用通常的固相反应工艺制备了Gd2（WO4）3陶瓷，在低场（脉150V／mm）下测试了样品的电学行为和介电常数随温度的变化。结果表明：随温度的升高，样品首先呈现出线性的Ohm特征，在250℃以后开始呈现出半导体特征下的非线性电学行为，并且这种非线性随温度的升高而增大；样品的介电常数和损耗因子在320℃350℃有明显的变化。XRD分析表明：样品中存在Gd2（WO4）3主晶相和W20O58次晶相。用WO3的相变可以简单解释上述实验结果。
采用通常的固相反应工艺制备了Gd2（WO4）3陶瓷，在低场（脉150V／mm）下测试了样品的电学行为和介电常数随温度的变化。结果表明：随温度的升高，样品首先呈现出线性的Ohm特征，在250℃以后开始呈现出半导体特征下的非线性电学行为，并且这种非线性随温度的升高而增大；样品的介电常数和损耗因子在320℃350℃有明显的变化。XRD分析表明：样品中存在Gd2（WO4）3主晶相和W20O58次晶相。用WO3的相变可以简单解释上述实验结果。
17 Effect of Rare Earth Modifier Treatment on Interlaminar Shear Strength of Aramid/Epoxy Composites
2005, 34(12):1917-1920.
Abstract:
分别采用稀土改性剂（RES）和环氧氯丙烷（ECP）接枝改性方法对F-12芳纶纤维表面进行改性处理，探讨了RES浓度对于芳纶／环氧复合材料层问剪切强度（ILSS）的影响，初步分析了RES对于F-12芳纶纤维表面作用的机理，应用SEM对复合材料层问剪切断口进行分析，并考察了稀土改性剂处理对于纤维强度的影响。实验结果表明：采用RES进行表面改性处理，稀土元素通过配位化学反应，能够提高芳纶纤维表面活性基团的浓度，从而提高芳纶纤维和环氧树脂基体的界面结合力；当稀十元素含量（ω,％）为0．5时，复合材料的层问剪切强度最好；稀土改性剂处理对于纤维本身的强度几乎没有影响。
分别采用稀土改性剂（RES）和环氧氯丙烷（ECP）接枝改性方法对F-12芳纶纤维表面进行改性处理，探讨了RES浓度对于芳纶／环氧复合材料层问剪切强度（ILSS）的影响，初步分析了RES对于F-12芳纶纤维表面作用的机理，应用SEM对复合材料层问剪切断口进行分析，并考察了稀土改性剂处理对于纤维强度的影响。实验结果表明：采用RES进行表面改性处理，稀土元素通过配位化学反应，能够提高芳纶纤维表面活性基团的浓度，从而提高芳纶纤维和环氧树脂基体的界面结合力；当稀十元素含量（ω,％）为0．5时，复合材料的层问剪切强度最好；稀土改性剂处理对于纤维本身的强度几乎没有影响。
2005, 34(12):1921-1925.
Abstract:
The Gibbs free energy changes of the reactions of magnesium and its alloy with some materials were calculated at high temperature. The possibilities of the reactions were analyzed by free energy criterion .The results show that SiC and ZrB2 have good stability to liquid magnesium and its alloy and they are the good materials of crucible used for magnesium and its alloy melting. The stability of SiC in the liquid magnesium and its alloy was tested by experiment.
The Gibbs free energy changes of the reactions of magnesium and its alloy with some materials were calculated at high temperature. The possibilities of the reactions were analyzed by free energy criterion .The results show that SiC and ZrB2 have good stability to liquid magnesium and its alloy and they are the good materials of crucible used for magnesium and its alloy melting. The stability of SiC in the liquid magnesium and its alloy was tested by experiment.
Zhang Guojun
,
Sun Yuanjun
,
Niu Rongmei
,
Sun Jun
,
Wei Jianfeng
,
Lan Yonggang
,
Zhao Baohua
,
Yang Liuxiao
,
Ma Baoping
2005, 34(12):1926-1929.
Abstract:
The rare earth lanthanum oxide doped molybdenum alloys containing different volume fraction lanthanum oxide particles were prepared by powder metallurgical processing. The microstructure and mechanical properties of the alloys were examined. It is found that the alloy has the fine lanthanum oxide particles and fine grain as well as high yield strength. The strengthening mechanism of the alloy is analyzed and explained in three aspects: matrix strengthening, fine grain size strengthening yielding Hall-Petch relationship, and fine particles strengthening according to the Orowan model. The quantitative relationships between the yield strengths of the alloys and the sizes, volume fraction of lanthanum oxide particles and the grain sizes were also presented.
The rare earth lanthanum oxide doped molybdenum alloys containing different volume fraction lanthanum oxide particles were prepared by powder metallurgical processing. The microstructure and mechanical properties of the alloys were examined. It is found that the alloy has the fine lanthanum oxide particles and fine grain as well as high yield strength. The strengthening mechanism of the alloy is analyzed and explained in three aspects: matrix strengthening, fine grain size strengthening yielding Hall-Petch relationship, and fine particles strengthening according to the Orowan model. The quantitative relationships between the yield strengths of the alloys and the sizes, volume fraction of lanthanum oxide particles and the grain sizes were also presented.
2005, 34(12):1930-1934.
Abstract:
以不同的凝固速率制备了Cu-10Ag亚共晶合金。铸态结构由初生Ag沉淀,(Cu+Ag)共晶和Cu相组成。采用大变形制备了Cu-10Ag合金原位纤维复合材料。其中由初生Ag沉淀相所形成的Ag纤维具有较大直径(d)并可用幂指数关系d=C·exp(-0.228η)拟合,式中η是真实应变,C是与合金原始晶体尺寸有关的系数,而由(Cu+Ag)共晶中的Ag层所形成的Ag纤维具有更细直径(几纳米)。低温中间热处理可进一步细化Ag纤维尺寸和改进性能。经热机械处理的Cu-10Ag合金原位纳米纤维复合材料具有高强度(σb＞1.5 GPa)和高电导率(＞60％IACS)。大变形Cu-10Ag合金原位纳米纤维复合材料显示了两阶段强化效应。讨论了影响Ag纤维尺寸的因素和复合材料的强化与形变机制。
以不同的凝固速率制备了Cu-10Ag亚共晶合金。铸态结构由初生Ag沉淀,(Cu+Ag)共晶和Cu相组成。采用大变形制备了Cu-10Ag合金原位纤维复合材料。其中由初生Ag沉淀相所形成的Ag纤维具有较大直径(d)并可用幂指数关系d=C·exp(-0.228η)拟合,式中η是真实应变,C是与合金原始晶体尺寸有关的系数,而由(Cu+Ag)共晶中的Ag层所形成的Ag纤维具有更细直径(几纳米)。低温中间热处理可进一步细化Ag纤维尺寸和改进性能。经热机械处理的Cu-10Ag合金原位纳米纤维复合材料具有高强度(σb＞1.5 GPa)和高电导率(＞60％IACS)。大变形Cu-10Ag合金原位纳米纤维复合材料显示了两阶段强化效应。讨论了影响Ag纤维尺寸的因素和复合材料的强化与形变机制。
Guo Hongzhen~
,
Zhang Wei~
,
Zhao Zhanglong~
,
Yao Zekun~
,
Guo Yingguang~
,
Wang Baoshan~
,
Zhao Yongqing~
,
Qu Henglei~
2005, 34(12):1935-1939.
Abstract:
研究了新型高强高韧高损伤容限TC21钛合金的超塑性拉伸变形行为及组织演化规律。结果表明,TC21合金具有良好的超塑性和较宽的超塑性温度-应变速率范围(720℃～960℃,5.5×10~(-5)／s～1.1×10~(-2)／s)。在最佳超塑性条件下(900℃,3.3×10~(-4)／s),平均延伸率达到980％,最高延伸率达到1309％,平均流动应力仅为19.5 MPa。在超塑性拉伸过程中,试样变形区将发生明显的动态再结晶,使原始条状初生α相破断、细化和等轴化,促进超塑性的提高。随着变形温度提高、变形量增大和变形时间加长,将发生聚集再结晶,使再结晶α相合并长大成不规则的大片状,引起显微组织明显粗化,断口表面起伏增加。在最佳超塑性条件下,断口中形成了大而深的空洞,晶界滑动和晶间断裂特征明显。
研究了新型高强高韧高损伤容限TC21钛合金的超塑性拉伸变形行为及组织演化规律。结果表明,TC21合金具有良好的超塑性和较宽的超塑性温度-应变速率范围(720℃～960℃,5.5×10~(-5)／s～1.1×10~(-2)／s)。在最佳超塑性条件下(900℃,3.3×10~(-4)／s),平均延伸率达到980％,最高延伸率达到1309％,平均流动应力仅为19.5 MPa。在超塑性拉伸过程中,试样变形区将发生明显的动态再结晶,使原始条状初生α相破断、细化和等轴化,促进超塑性的提高。随着变形温度提高、变形量增大和变形时间加长,将发生聚集再结晶,使再结晶α相合并长大成不规则的大片状,引起显微组织明显粗化,断口表面起伏增加。在最佳超塑性条件下,断口中形成了大而深的空洞,晶界滑动和晶间断裂特征明显。
2005, 34(12):1940-1943.
Abstract:
研究了SPZ钛合金的超塑性变形及其变形前后的显微组织。研究结果表明,大塑性变形后,SPZ合金轧棒组织为利于超塑性的细小均匀的等轴组织。SPZ合金在740℃～800℃之间具有超塑性,在760℃,初始应变速率为1.11×10~(-3)s~(-1)时,合金的最大超塑延伸率可达2149％；应变速率为1.11×10.~(-2)s~(-1)时,超塑延伸率仍可达1380％。超塑性变形后的晶粒尺寸比变形前粗大,变形温度越高,晶粒长大程度越大。变形前合金的晶粒尺寸为0.89μm；应变速率为2.22×10~(-3)s~(-1)时,在740℃,760℃,780℃变形后晶粒尺寸分别为1.51μm,2.33μm,3.21μm。SPZ合金超塑性变形的微观机制足以晶界滑动为主,晶内变形以及位错蠕变起协调作用。合金超塑性变形与类流态的关系还有待深入研究。
研究了SPZ钛合金的超塑性变形及其变形前后的显微组织。研究结果表明,大塑性变形后,SPZ合金轧棒组织为利于超塑性的细小均匀的等轴组织。SPZ合金在740℃～800℃之间具有超塑性,在760℃,初始应变速率为1.11×10~(-3)s~(-1)时,合金的最大超塑延伸率可达2149％；应变速率为1.11×10.~(-2)s~(-1)时,超塑延伸率仍可达1380％。超塑性变形后的晶粒尺寸比变形前粗大,变形温度越高,晶粒长大程度越大。变形前合金的晶粒尺寸为0.89μm；应变速率为2.22×10~(-3)s~(-1)时,在740℃,760℃,780℃变形后晶粒尺寸分别为1.51μm,2.33μm,3.21μm。SPZ合金超塑性变形的微观机制足以晶界滑动为主,晶内变形以及位错蠕变起协调作用。合金超塑性变形与类流态的关系还有待深入研究。
2005, 34(12):1944-1947.
Abstract:
研究了用改进Lely法制备SiC单晶的过程中坩埚石墨化度对物质传输和晶体生长速度的影响。在不同温度下进行石墨化处理得到了实验所用的坩埚。用XRD方法定量测定了晶体生长前坩埚的石墨化度，并用SEM分析了晶体生长后坩埚内壁的反应情况。实验结果表明，石墨坩埚在SiC晶体生长过程中是一个非常重要的碳源提供者：当坩埚的石墨化程度较低时，晶体的生长速度快，生长速度由生长温度所控制；随着坩埚石墨化程度的提高，晶体生长速度减慢并由坩埚石墨化度所控制；当石墨化度进一步提高的时候，籽晶被碳化，晶体不能正常生长。
研究了用改进Lely法制备SiC单晶的过程中坩埚石墨化度对物质传输和晶体生长速度的影响。在不同温度下进行石墨化处理得到了实验所用的坩埚。用XRD方法定量测定了晶体生长前坩埚的石墨化度，并用SEM分析了晶体生长后坩埚内壁的反应情况。实验结果表明，石墨坩埚在SiC晶体生长过程中是一个非常重要的碳源提供者：当坩埚的石墨化程度较低时，晶体的生长速度快，生长速度由生长温度所控制；随着坩埚石墨化程度的提高，晶体生长速度减慢并由坩埚石墨化度所控制；当石墨化度进一步提高的时候，籽晶被碳化，晶体不能正常生长。
Zhang Qing
,
Li Zhongkui
,
Zheng Yuzhu
,
Zhang Junliang
,
Hu Zhongwu
,
Zhang Tingjie
,
Yin Tao
,
Ding Xuefeng
,
Ding Xu
2005, 34(12):1948-1951.
Abstract:
报道了φ31mm×500mm大尺寸定向生长钼-铌合金单晶的研制情况,介绍了原料选用与制备时所必需遵循的原则,论述了坯料直径与生长单晶直径的关系,并分析了所研制的定向生长单晶的晶向偏角、力学性能和组织结构。
报道了φ31mm×500mm大尺寸定向生长钼-铌合金单晶的研制情况,介绍了原料选用与制备时所必需遵循的原则,论述了坯料直径与生长单晶直径的关系,并分析了所研制的定向生长单晶的晶向偏角、力学性能和组织结构。
2005, 34(12):1952-1956.
Abstract:
The change of morphology of Cr phase, mechanical properties and electrical conductivity of CuCr alloy under different cold deformation quantity and heat treatment were studied. The results show that when reduction is up to 70%, Cr particles are deformed heavily, and some of Cr particles are broken. After the following high temperature heat treatment, broken Cr particles in the microstructure dissolves, and tend to turn into spherical morphology. As a results the mechanical properties and electrical conductivity of CuCr alloy are improved by means of proper deformation and heat treatment, and its mechanism was analyzed from microstructure.
The change of morphology of Cr phase, mechanical properties and electrical conductivity of CuCr alloy under different cold deformation quantity and heat treatment were studied. The results show that when reduction is up to 70%, Cr particles are deformed heavily, and some of Cr particles are broken. After the following high temperature heat treatment, broken Cr particles in the microstructure dissolves, and tend to turn into spherical morphology. As a results the mechanical properties and electrical conductivity of CuCr alloy are improved by means of proper deformation and heat treatment, and its mechanism was analyzed from microstructure.
2005, 34(12):1957-1960.
Abstract:
首次采用浸渍法制备了硅钨钼酸掺杂聚苯胺催化剂H4SiW6Mo6O40／PAn。以环己酮和1，2．丙二醇为原料合成环己酮1，2-丙二醇缩酮。探讨了硅钨钼酸掺杂聚苯胺催化剂对缩酮反应的催化活性，较系统地研究了原料量比，催化剂用量，反应时间诸因素对产品收率的影响。实验表明：硅钨钼酸掺杂聚苯胺是合成环己酮1,2-丙二醇缩酮的良好催化剂，在n（环己酮）：n（1，2-丙二醇）=1：1．7，催化剂用量为反应物料总质量的1．0％，环己烷为带水剂，反应时间1．0h的优化条件下，环己酮1．2-丙二醇缩酮的收率可达84．6％。
首次采用浸渍法制备了硅钨钼酸掺杂聚苯胺催化剂H4SiW6Mo6O40／PAn。以环己酮和1，2．丙二醇为原料合成环己酮1，2-丙二醇缩酮。探讨了硅钨钼酸掺杂聚苯胺催化剂对缩酮反应的催化活性，较系统地研究了原料量比，催化剂用量，反应时间诸因素对产品收率的影响。实验表明：硅钨钼酸掺杂聚苯胺是合成环己酮1,2-丙二醇缩酮的良好催化剂，在n（环己酮）：n（1，2-丙二醇）=1：1．7，催化剂用量为反应物料总质量的1．0％，环己烷为带水剂，反应时间1．0h的优化条件下，环己酮1．2-丙二醇缩酮的收率可达84．6％。
2005, 34(12):1961-1964.
Abstract:
采用高温固溶法制备Sc2O3（Dy2O3）和Yb2O3复合掺杂YSZ电解质材料，研究了复合掺杂对YSZ烧结性和电性能的影响。结果表明：随着Sc2O3含量的增加，试样烧结密度降低（1600℃烧结密度由5．82g／cm^3降至5．24g／cm^3），而Dy2O3却能提高烧结密度（1600℃烧结密度由5．63g／cm^3增至5．86g／cm^3）：当掺杂总量x，％）为8～8．6时，材料电导率得到大幅度提高（1000℃时，0．18S／cm）；1nσ-1000／T呈现较好的线性关系，说明电导率σ与温度T之间关系符合Arrhenius公式；XRD分析表明复合掺杂YSZ电解质材料晶格常数有所增大，对提高电导率起积极作用；复合添加剂促进了晶粒生长，尤其是含Dy试样晶粒尺寸较大。
采用高温固溶法制备Sc2O3（Dy2O3）和Yb2O3复合掺杂YSZ电解质材料，研究了复合掺杂对YSZ烧结性和电性能的影响。结果表明：随着Sc2O3含量的增加，试样烧结密度降低（1600℃烧结密度由5．82g／cm^3降至5．24g／cm^3），而Dy2O3却能提高烧结密度（1600℃烧结密度由5．63g／cm^3增至5．86g／cm^3）：当掺杂总量x，％）为8～8．6时，材料电导率得到大幅度提高（1000℃时，0．18S／cm）；1nσ-1000／T呈现较好的线性关系，说明电导率σ与温度T之间关系符合Arrhenius公式；XRD分析表明复合掺杂YSZ电解质材料晶格常数有所增大，对提高电导率起积极作用；复合添加剂促进了晶粒生长，尤其是含Dy试样晶粒尺寸较大。
2005, 34(12):1965-1968.
Abstract:
介绍了化学气相沉积法(CVD)制备难熔金属钼膜层的原理和方法。以MoF_6和H_2为原料,采用化学气相沉积法在纯铜基体上沉积出难熔金属钼膜层。分析研究了沉积层的组织、结构和硬度。实验结果表明：沉积膜层显微组织随沉积温度变化而不同,沉积温度较低时,沉积层显微组织为细晶层状结构,沉积层硬度可达677×9.8 MPa：沉积温度较高时,沉积层显微组织为致密的柱状晶,硬度稍高于一般烧结钼的硬度。
介绍了化学气相沉积法(CVD)制备难熔金属钼膜层的原理和方法。以MoF_6和H_2为原料,采用化学气相沉积法在纯铜基体上沉积出难熔金属钼膜层。分析研究了沉积层的组织、结构和硬度。实验结果表明：沉积膜层显微组织随沉积温度变化而不同,沉积温度较低时,沉积层显微组织为细晶层状结构,沉积层硬度可达677×9.8 MPa：沉积温度较高时,沉积层显微组织为致密的柱状晶,硬度稍高于一般烧结钼的硬度。
2005, 34(12):1969-1973.
Abstract:
利用预涂Si粉,Ti+Si粉的方法对TiAl合金进行电子束表面合金化,“原位”制得了以高硬度金属间化合物Ti_Si_3为增强相的表面改性层。利用光学显微镜、扫描电子显微镜、能谱仪及X射线衍射仪分析和研究了电子束表面改性层的显微组织结构；同时测试了沿改性层深度方向的硬度分布。结果表明,表面改性层由TiAl,Ti_3Al,Ti_Si_3相组成,Ti_5Si_3相的形态及分布沿层深呈均匀分布；改性层具有较高的显微硬度(HV),最高达895×9.8 MPa,约是基体的3倍。
利用预涂Si粉,Ti+Si粉的方法对TiAl合金进行电子束表面合金化,“原位”制得了以高硬度金属间化合物Ti_Si_3为增强相的表面改性层。利用光学显微镜、扫描电子显微镜、能谱仪及X射线衍射仪分析和研究了电子束表面改性层的显微组织结构；同时测试了沿改性层深度方向的硬度分布。结果表明,表面改性层由TiAl,Ti_3Al,Ti_Si_3相组成,Ti_5Si_3相的形态及分布沿层深呈均匀分布；改性层具有较高的显微硬度(HV),最高达895×9.8 MPa,约是基体的3倍。
2005, 34(12):1974-1977.
Abstract:
对机械合金化SiC／MoSi2的先驱粉体及随后反应烧结制备SiC／MoSi2复合材料工艺研究表明：经机械合金化的先驱粉体主要成分为MoSi2。反应烧结温度在Si的熔点以上时，由于Si在MoSi2颗粒的表面的润湿铺展，导致烧结1h后的产物为Mo5Si3C，MoSi2，SiC和单质Si；在Si的熔点以下时，对过渡相Mo5Si3C的产生有一定抑制作用，反应烧结过程中只有少量过渡相Mo5Si3C出现；通过1600℃真空热处理2h可以基本上消除Mo5Si3C相，得到只有MoSi2和SiC两相的均匀材料。
对机械合金化SiC／MoSi2的先驱粉体及随后反应烧结制备SiC／MoSi2复合材料工艺研究表明：经机械合金化的先驱粉体主要成分为MoSi2。反应烧结温度在Si的熔点以上时，由于Si在MoSi2颗粒的表面的润湿铺展，导致烧结1h后的产物为Mo5Si3C，MoSi2，SiC和单质Si；在Si的熔点以下时，对过渡相Mo5Si3C的产生有一定抑制作用，反应烧结过程中只有少量过渡相Mo5Si3C出现；通过1600℃真空热处理2h可以基本上消除Mo5Si3C相，得到只有MoSi2和SiC两相的均匀材料。
2005, 34(12):1978-1981.
Abstract:
采用直接化学镀镍的方法,得到了光亮且均匀、致密的Ni-P镀层。在分析镀层形貌、化学成分和组织结构的基础上,测定了镀层厚度、硬度、结合力、阻抗及耐蚀性。结果表明：改进后的化学镀镍层与基体结合良好；硬度达479×9.8 MPa,400℃热处理后可提高至826X9.8 MPa；阻抗为0.4 Ω,且随热处理温度的提高呈下降趋势；镀层耐腐蚀性能良好,热处理后耐蚀性有所下降。
采用直接化学镀镍的方法,得到了光亮且均匀、致密的Ni-P镀层。在分析镀层形貌、化学成分和组织结构的基础上,测定了镀层厚度、硬度、结合力、阻抗及耐蚀性。结果表明：改进后的化学镀镍层与基体结合良好；硬度达479×9.8 MPa,400℃热处理后可提高至826X9.8 MPa；阻抗为0.4 Ω,且随热处理温度的提高呈下降趋势；镀层耐腐蚀性能良好,热处理后耐蚀性有所下降。
2005, 34(12):1982-1984.
Abstract:
The thermal conductivity of W-Cu composites is affected by the position where they were placed in during infiltrating. The W-Cu composites after infiltrating were kept at a certain temperature for some hours with the protection of hydrogen and then cooled down to room temperature by different means. By X-ray diffraction experiment, tungsten phase is found to be under compression and copper phase under tension. The value of the residual stresses increases with the cooling rate, while the thermal conductivity, inversely. The coefficient of thermal expansion(CTE) mismatch of tungsten and copper led to the significant amount of thermal stresses at the interface and low thermal conductivity. The effect of the residual stresses on the thermal conductivity, as well as its mechanism was analyzed.
The thermal conductivity of W-Cu composites is affected by the position where they were placed in during infiltrating. The W-Cu composites after infiltrating were kept at a certain temperature for some hours with the protection of hydrogen and then cooled down to room temperature by different means. By X-ray diffraction experiment, tungsten phase is found to be under compression and copper phase under tension. The value of the residual stresses increases with the cooling rate, while the thermal conductivity, inversely. The coefficient of thermal expansion(CTE) mismatch of tungsten and copper led to the significant amount of thermal stresses at the interface and low thermal conductivity. The effect of the residual stresses on the thermal conductivity, as well as its mechanism was analyzed.
2005, 34(12):1985-1989.
Abstract:
探讨了高温下喷丸强化（SP）因素（残余压应力引入、表面粗糙度增大、表面加工硬化等）对Ti811钛合金微动疲劳（FF）抗力的作用规律和机制。结果表明，SP处理可以有效地提高350℃高温下Ti811合金的微动疲劳抗力，但对500℃下FF抗力有不利影响：SP引入的表层残余压应力增加裂纹闭合力，是SP提高350℃高温下钛合金FF抗力最为重要的因素，SP表面加工硬化的作用为次要因素；SP造成的粗糙度增大在350℃和500℃高温下对钛合金的FF抗力呈现出不利的作用，原因是表面机械损伤的影响突出，这种影响与残余压应力的存在状态有关。
探讨了高温下喷丸强化（SP）因素（残余压应力引入、表面粗糙度增大、表面加工硬化等）对Ti811钛合金微动疲劳（FF）抗力的作用规律和机制。结果表明，SP处理可以有效地提高350℃高温下Ti811合金的微动疲劳抗力，但对500℃下FF抗力有不利影响：SP引入的表层残余压应力增加裂纹闭合力，是SP提高350℃高温下钛合金FF抗力最为重要的因素，SP表面加工硬化的作用为次要因素；SP造成的粗糙度增大在350℃和500℃高温下对钛合金的FF抗力呈现出不利的作用，原因是表面机械损伤的影响突出，这种影响与残余压应力的存在状态有关。
2005, 34(12):1990-1993.
Abstract:
The research is carried out about the microstructure, mechanical properties, deformation and fracture feature of 93 W alloy deformed by hydrostatic extrusion. The result shows that the strength of tungsten alloy increases with the increase of the deformation amount, the elongation of tungsten alloy decreases with the increase of the deformation amount; The deformation initiates from binder phase. The deformation is typical two-phase harmonious deformation, the crack generate from the W-W interface; The ratio of W particle cleavage in fracture surface of deformed tungsten alloy is greater than that of undeformed.
The research is carried out about the microstructure, mechanical properties, deformation and fracture feature of 93 W alloy deformed by hydrostatic extrusion. The result shows that the strength of tungsten alloy increases with the increase of the deformation amount, the elongation of tungsten alloy decreases with the increase of the deformation amount; The deformation initiates from binder phase. The deformation is typical two-phase harmonious deformation, the crack generate from the W-W interface; The ratio of W particle cleavage in fracture surface of deformed tungsten alloy is greater than that of undeformed.
2005, 34(12):1994-1997.
Abstract:
采用液相烧结法（LPS）制备了TiC／Ti复合材料，借助X射线衍射（XRD）分析了复合材料的相构成。对TiCFFi复合材料进行了高温压缩和高温挤压实验，利用扫描电镜（SEM）和光学显微镜（OM）分析了复合材料高温变形前后的微观组织。实验结果表明：基体Ti与烧结助剂中的Cu发生反应生成玻璃相TiCu2。在高温塑性变形过程中，由于液相TiCu2的存在，使复合材料表现出良好的高温塑性变形能力，压缩率达到72．9％，挤压比为16：1：复合材料高温塑性变形后，材料中的孔洞明显减少，致密度得到提高，组织成分保持稳定：处于液相状态的TiCu2高温挤压后，细化成尺寸为1μm～2μm的小颗粒，均匀分布于基体Ti颗粒的周围。
采用液相烧结法（LPS）制备了TiC／Ti复合材料，借助X射线衍射（XRD）分析了复合材料的相构成。对TiCFFi复合材料进行了高温压缩和高温挤压实验，利用扫描电镜（SEM）和光学显微镜（OM）分析了复合材料高温变形前后的微观组织。实验结果表明：基体Ti与烧结助剂中的Cu发生反应生成玻璃相TiCu2。在高温塑性变形过程中，由于液相TiCu2的存在，使复合材料表现出良好的高温塑性变形能力，压缩率达到72．9％，挤压比为16：1：复合材料高温塑性变形后，材料中的孔洞明显减少，致密度得到提高，组织成分保持稳定：处于液相状态的TiCu2高温挤压后，细化成尺寸为1μm～2μm的小颗粒，均匀分布于基体Ti颗粒的周围。
2005, 34(12):1998-2001.
Abstract:
The extreme high temperature oxidation behavior of commercial pure titanium was researched by Gleeble-1500 thermal simulator. The results show that the weight gain increase continually with the increase of the oxidation temperature and the time of holding temperature. There are several oxide layers at extreme high temperature. Oxygen diffuses from the path in the cracked outer oxide layer into rather compact inner oxide layer and further into metal, which actualize the commercial pure titanium's oxidation at extreme high temperature.
The extreme high temperature oxidation behavior of commercial pure titanium was researched by Gleeble-1500 thermal simulator. The results show that the weight gain increase continually with the increase of the oxidation temperature and the time of holding temperature. There are several oxide layers at extreme high temperature. Oxygen diffuses from the path in the cracked outer oxide layer into rather compact inner oxide layer and further into metal, which actualize the commercial pure titanium's oxidation at extreme high temperature.
2005, 34(12):2002-2005.
Abstract:
HDDR法生产Sm2Fe17Nx磁粉的关键是获得细小的晶粒。通过XRD，SEM，EDX等手段研究了Sm2Fe17合金粉在脱氢-再化合过程中的相及微观结构的演化规律。结果表明：在真空条件下，650℃时，已经歧化为SmHx和α-Fe的合金粉的脱氢-再化合开始，先形成非稳定的TbCu7结构的SmFe7相，随着再化合温度的升高，SmFe7相逐渐向稳态相Sm2Fe17转变，在850℃时转变完全；在再化合过程中，合金粉的颗粒大小不发生变化，但内部晶粒已经明显细化；850℃脱氢-再化合lh。晶粒大小约50nm。
HDDR法生产Sm2Fe17Nx磁粉的关键是获得细小的晶粒。通过XRD，SEM，EDX等手段研究了Sm2Fe17合金粉在脱氢-再化合过程中的相及微观结构的演化规律。结果表明：在真空条件下，650℃时，已经歧化为SmHx和α-Fe的合金粉的脱氢-再化合开始，先形成非稳定的TbCu7结构的SmFe7相，随着再化合温度的升高，SmFe7相逐渐向稳态相Sm2Fe17转变，在850℃时转变完全；在再化合过程中，合金粉的颗粒大小不发生变化，但内部晶粒已经明显细化；850℃脱氢-再化合lh。晶粒大小约50nm。
2005, 34(12):2006-2008.
Abstract:
用熔体快淬法和晶化热处理工艺制备Nd10．5Fe78-xCo5ZrxB6．5（x=0，2，3，4，5）纳米晶双相永磁材料，研究了其磁性能与结构的变化。结果表明：适量地添加（2at％）Zr能显著提高合金的内禀矫顽力，并且可以有效抑制合金中的软、硬磁相的晶粒长大，获得晶粒尺寸为20nm的微观结构，使得合金中的软磁相和硬磁相发生比较充分的交换耦合作用，从而有效地提高合金的磁性能。
用熔体快淬法和晶化热处理工艺制备Nd10．5Fe78-xCo5ZrxB6．5（x=0，2，3，4，5）纳米晶双相永磁材料，研究了其磁性能与结构的变化。结果表明：适量地添加（2at％）Zr能显著提高合金的内禀矫顽力，并且可以有效抑制合金中的软、硬磁相的晶粒长大，获得晶粒尺寸为20nm的微观结构，使得合金中的软磁相和硬磁相发生比较充分的交换耦合作用，从而有效地提高合金的磁性能。
2005, 34(12):2009-2012.
Abstract:
Al-Ti-C master alloys used as grain refiners of the aluminum and its alloys have been prepared by self-propagating high-temperature synthesis (SHS) technology. The influence of pressure, diameter and preheating temperature of green-pellet on combustion temperature (T_c) during preparing Al-Ti-C master alloy and the microstructure of synthesized product has been investigated. The results show that synthesized master alloy consist of Al, Al_3Ti and TiC, and green-pellet pressure and preheating temperature have remarkable influence on combustion temperature (T_c) and microstructure of synthesized product. However, in this study, the influence of green-pellet diameter is unapparent.
Al-Ti-C master alloys used as grain refiners of the aluminum and its alloys have been prepared by self-propagating high-temperature synthesis (SHS) technology. The influence of pressure, diameter and preheating temperature of green-pellet on combustion temperature (T_c) during preparing Al-Ti-C master alloy and the microstructure of synthesized product has been investigated. The results show that synthesized master alloy consist of Al, Al_3Ti and TiC, and green-pellet pressure and preheating temperature have remarkable influence on combustion temperature (T_c) and microstructure of synthesized product. However, in this study, the influence of green-pellet diameter is unapparent.
2005, 34(12):2013-2016.
Abstract:
采用CVD（Chemical Vapor Deposition）法沉积的钨涂层有[100]／[111]／[110]择优取向。择优取向主要受气体组分、流动速度、温度等因素的影响。研究了钼基体上CVD钨涂层的表面形貌和织构、涂层界面的元素分布、涂层的抗热震性能及高温扩散性能。结果显示：钨涂层与基体钼有2μm左右的互扩散层且钼在钨中的扩散速度更高；涂层在通H2条件下，进行室温→1400℃→室温20次循环后涂层不脱落、界面没有明显变化，涂层结合力好；涂层界面上的杂质元素氧等影响涂层的结合性能。
采用CVD（Chemical Vapor Deposition）法沉积的钨涂层有[100]／[111]／[110]择优取向。择优取向主要受气体组分、流动速度、温度等因素的影响。研究了钼基体上CVD钨涂层的表面形貌和织构、涂层界面的元素分布、涂层的抗热震性能及高温扩散性能。结果显示：钨涂层与基体钼有2μm左右的互扩散层且钼在钨中的扩散速度更高；涂层在通H2条件下，进行室温→1400℃→室温20次循环后涂层不脱落、界面没有明显变化，涂层结合力好；涂层界面上的杂质元素氧等影响涂层的结合性能。
