Volume 35,Issue 1,2006 Table of Contents
2006, 35(1).
Abstract:
采用热重-差热(TG-DTA)与气-质联用(GC-MS)研究了CVD技术制备钯膜材料的前驱体乙酰丙酮钯[Pd(acac)2]的热分解行为。通过对比其在空气和氩气两种气氛、不同温度下的热裂解产物,认为在以乙酰丙酮钯为前驱体通过CVD技术制备钯膜时,空气比氩气更适合做载气。
采用热重-差热(TG-DTA)与气-质联用(GC-MS)研究了CVD技术制备钯膜材料的前驱体乙酰丙酮钯[Pd(acac)2]的热分解行为。通过对比其在空气和氩气两种气氛、不同温度下的热裂解产物,认为在以乙酰丙酮钯为前驱体通过CVD技术制备钯膜时,空气比氩气更适合做载气。
2006, 35(1):1-4.
Abstract:
研究了Ti-45Al-5Nb（at％）和Ti-45Al-5Nb-0．3Y（at％）合金的铸态显微组织。结果表明：稀土Y的添加改变了Ti-45Al-5Nb合金的铸态显微组织，促进了等轴晶粒的形成，极大地细化了晶粒；稀土Y主要富集在等轴晶粒的晶界处，并呈断续网络状分布，还有极少量的稀土呈小颗粒分布在晶粒内部；与Ti-45l-5Nb合金相比，Ti-45Al-5Nb-0．3Y合金除了γ和α2相外，还形成了富集Al和Y的富稀土 相-YAl2相；在合金凝固过程中，稀土Y能够提高TiAl合金的形核率，同时稀土Y在固液界面前沿的富集抑制了初生声相的生长，并且后者对晶粒的细化起主要作用。
研究了Ti-45Al-5Nb（at％）和Ti-45Al-5Nb-0．3Y（at％）合金的铸态显微组织。结果表明：稀土Y的添加改变了Ti-45Al-5Nb合金的铸态显微组织，促进了等轴晶粒的形成，极大地细化了晶粒；稀土Y主要富集在等轴晶粒的晶界处，并呈断续网络状分布，还有极少量的稀土呈小颗粒分布在晶粒内部；与Ti-45l-5Nb合金相比，Ti-45Al-5Nb-0．3Y合金除了γ和α2相外，还形成了富集Al和Y的富稀土 相-YAl2相；在合金凝固过程中，稀土Y能够提高TiAl合金的形核率，同时稀土Y在固液界面前沿的富集抑制了初生声相的生长，并且后者对晶粒的细化起主要作用。
2006, 35(1):5-8.
Abstract:
采用X射线衍射、SEM、EDS等分析方法，研究了铁元素对光束堆焊合成NiAl金属间化合物层的成形和组织结构的影响规律。结果表明，光束堆焊镍铝混合粉制备NiAl金属间化合物层时，NiAl的高熔点导致堆焊层成形困难。在镍铝混合粉中加入适量铁粉（11at％～28at％）可以降低堆焊合金体系的熔点、改善堆焊层成形。随着铁粉加入量的增加，堆焊层的稀释率呈现先增加后降低的趋势，过多的铁粉加入量（43at％）将使熔池金属不能润湿母材。铁元素的引入使堆焊层中析出了Fe3Al相，随着堆焊层中含Fe量的增加，Fe3Al的析出量增加，堆焊层的微观组织为NiAl柱状晶和柱状晶间的Fe3Al条状相。
采用X射线衍射、SEM、EDS等分析方法，研究了铁元素对光束堆焊合成NiAl金属间化合物层的成形和组织结构的影响规律。结果表明，光束堆焊镍铝混合粉制备NiAl金属间化合物层时，NiAl的高熔点导致堆焊层成形困难。在镍铝混合粉中加入适量铁粉（11at％～28at％）可以降低堆焊合金体系的熔点、改善堆焊层成形。随着铁粉加入量的增加，堆焊层的稀释率呈现先增加后降低的趋势，过多的铁粉加入量（43at％）将使熔池金属不能润湿母材。铁元素的引入使堆焊层中析出了Fe3Al相，随着堆焊层中含Fe量的增加，Fe3Al的析出量增加，堆焊层的微观组织为NiAl柱状晶和柱状晶间的Fe3Al条状相。
2006, 35(1):9-12.
Abstract:
采用循环伏安电沉积技术在钛基上获得水合氧化钌(RuOx·nH2O),其比容量为105F/g。通过电化学测试(循环伏安、恒电流充放电)、X射线衍射(XRD)、扫描电镜(SEM)以及X射线光电子能谱(XPS)等方法研究了沉积物的电化学性质、物相及组成。结果表明:电沉积法获得的水合氧化钌呈非晶态结构,它由多氧化态钌混合羟基氧化物组成。在1.0mol·L-1H2SO4溶液中,该氧化物呈准电容特征,有较高电化学可逆性,可用作电化学电容器电极材料。
采用循环伏安电沉积技术在钛基上获得水合氧化钌(RuOx·nH2O),其比容量为105F/g。通过电化学测试(循环伏安、恒电流充放电)、X射线衍射(XRD)、扫描电镜(SEM)以及X射线光电子能谱(XPS)等方法研究了沉积物的电化学性质、物相及组成。结果表明:电沉积法获得的水合氧化钌呈非晶态结构,它由多氧化态钌混合羟基氧化物组成。在1.0mol·L-1H2SO4溶液中,该氧化物呈准电容特征,有较高电化学可逆性,可用作电化学电容器电极材料。
2006, 35(1):13-16.
Abstract:
采用基于有限元反射模型的SFS（shape from shading）算法对锆-4合金低周疲劳断口进行三维重建，定量描述了断口表面的三维形貌。然后，根据小岛法的基本理论，研究了断口三维形貌的分维计算方法，计算了一系列平行于断口表面的分维值。结果表明：在40％～60％高度范围内，根据小岛法作出周长L（η）-面积A（η）在双对数图上呈近似直线关系，表明Zr-4合金断口具有良好的分形特征；分形维数D变化范围为1．5809～1．6450，平均值1．603l，标准差0．0237。表明在此切割高度范围内，高度对分维值影响较小。
采用基于有限元反射模型的SFS（shape from shading）算法对锆-4合金低周疲劳断口进行三维重建，定量描述了断口表面的三维形貌。然后，根据小岛法的基本理论，研究了断口三维形貌的分维计算方法，计算了一系列平行于断口表面的分维值。结果表明：在40％～60％高度范围内，根据小岛法作出周长L（η）-面积A（η）在双对数图上呈近似直线关系，表明Zr-4合金断口具有良好的分形特征；分形维数D变化范围为1．5809～1．6450，平均值1．603l，标准差0．0237。表明在此切割高度范围内，高度对分维值影响较小。
2006, 35(1):17-20.
Abstract:
在电子探针测量的基础上,根据扩散理论和Ir-Re相图数据,建立了一个全新的Ir/Re两相扩散模型。计算得到在1200℃~2000℃时Ir基固溶体中的互扩散系数为:D=1.17×10-6exp(–1.80eV/kT)(cm2/s),Re基固溶体中的互扩散系数为:D=1.36×10-8exp(–1.21eV/kT)(cm2/s)。确定喷管中Ir/Re为晶界扩散。
在电子探针测量的基础上,根据扩散理论和Ir-Re相图数据,建立了一个全新的Ir/Re两相扩散模型。计算得到在1200℃~2000℃时Ir基固溶体中的互扩散系数为:D=1.17×10-6exp(–1.80eV/kT)(cm2/s),Re基固溶体中的互扩散系数为:D=1.36×10-8exp(–1.21eV/kT)(cm2/s)。确定喷管中Ir/Re为晶界扩散。
2006, 35(1):21-24.
Abstract:
Such experimental researches as XRD, SEM and TEM were conducted on the synthesized ceramic heat-resistant gradient material of TiC-Mo/W system prepared by combining SHS with the new method of HP. The result of XRD shows that the reaction product is no other than TiC and Mo/W. TEM analysis finds that TiC ceramic particle becomes a ellipsoidal distribution, tiny and relatively even particle, with Mo/W metal phase in-between; SEM indicates that the shape of multi-metal phase appears to be island-like and distributes in continuous gradient clouds. The compacting density, bending strength, fracture toughness and rigidity value of the synthesis can be prepared to be applicable gradient material structure under suitable pressure and temperature. In the course of SHS/HP, Mo/W distributes into ceramics TiC in the manner of gradient clouds along the sample grade direction. According to the research, the characteristics of the material is anisotropic and transversally isotropic along the direction and vertical grade direction respectively.
Such experimental researches as XRD, SEM and TEM were conducted on the synthesized ceramic heat-resistant gradient material of TiC-Mo/W system prepared by combining SHS with the new method of HP. The result of XRD shows that the reaction product is no other than TiC and Mo/W. TEM analysis finds that TiC ceramic particle becomes a ellipsoidal distribution, tiny and relatively even particle, with Mo/W metal phase in-between; SEM indicates that the shape of multi-metal phase appears to be island-like and distributes in continuous gradient clouds. The compacting density, bending strength, fracture toughness and rigidity value of the synthesis can be prepared to be applicable gradient material structure under suitable pressure and temperature. In the course of SHS/HP, Mo/W distributes into ceramics TiC in the manner of gradient clouds along the sample grade direction. According to the research, the characteristics of the material is anisotropic and transversally isotropic along the direction and vertical grade direction respectively.
2006, 35(1):25-28.
Abstract:
研究了镁基复合材料超塑性变形过程中SiC晶须织构的演化规律,并分析了其对孔洞行为的影响。超塑性拉伸试验在613K~723K,8.3×10-4s-1~8.3×10-2s-1条件下进行。在613K,1.67×10-2s-1初始应变速率下,获得了200%的延伸率。SiC晶须在超塑性变形过程中发展出强烈的<111>//ED纤维织构。SiC晶须的这种取向对晶界滑动有阻碍作用,不仅使孔洞易于萌生,也加速了其长大与连接。
研究了镁基复合材料超塑性变形过程中SiC晶须织构的演化规律,并分析了其对孔洞行为的影响。超塑性拉伸试验在613K~723K,8.3×10-4s-1~8.3×10-2s-1条件下进行。在613K,1.67×10-2s-1初始应变速率下,获得了200%的延伸率。SiC晶须在超塑性变形过程中发展出强烈的<111>//ED纤维织构。SiC晶须的这种取向对晶界滑动有阻碍作用,不仅使孔洞易于萌生,也加速了其长大与连接。
2006, 35(1):29-33.
Abstract:
A newly developed cost-effective processing route, in situ reactive infiltration technique, was utilized to fabricate 47.5vol.%TiC/AZ91D magnesium matrix composites. A comparative study was made on the tensile deformation behavior at room and elevated temperatures for the as synthesized composites and the matrix alloy magnesium AZ91D and their fracture characteristics were also analyzed as well. The results show that the TiC/Mg composites fabricated by in situ reactive infiltration process possess excellent high-temperature mechanical properties. The ultimate tensile strength of the matrix magnesium alloy AZ91D at 723 K and a strain rate of 0.001 s^-1 is 41.1 MPa, while that of TiC/Mg composites at the same deformation conditions increases by 120% and reaches 91.1 MPa. At room temperature, the ultimate tensile strength of the composites increases only by 23.4% as compared with the AZ91D alloy. The SEM observation of the morphologies for the fractured surfaces reveals that the fracture mode differs from one another in that the composites are of brittle characteristic at room and elevated temperatures due to its limited failure strain, whereas the fracture mode of the magnesium alloy has a transition from brittleness at room temperature towards ductileness at elevated temperature.
A newly developed cost-effective processing route, in situ reactive infiltration technique, was utilized to fabricate 47.5vol.%TiC/AZ91D magnesium matrix composites. A comparative study was made on the tensile deformation behavior at room and elevated temperatures for the as synthesized composites and the matrix alloy magnesium AZ91D and their fracture characteristics were also analyzed as well. The results show that the TiC/Mg composites fabricated by in situ reactive infiltration process possess excellent high-temperature mechanical properties. The ultimate tensile strength of the matrix magnesium alloy AZ91D at 723 K and a strain rate of 0.001 s^-1 is 41.1 MPa, while that of TiC/Mg composites at the same deformation conditions increases by 120% and reaches 91.1 MPa. At room temperature, the ultimate tensile strength of the composites increases only by 23.4% as compared with the AZ91D alloy. The SEM observation of the morphologies for the fractured surfaces reveals that the fracture mode differs from one another in that the composites are of brittle characteristic at room and elevated temperatures due to its limited failure strain, whereas the fracture mode of the magnesium alloy has a transition from brittleness at room temperature towards ductileness at elevated temperature.
2006, 35(1):34-38.
Abstract:
本文研究了铌离子注入对锆-4合金在400℃和500℃、10．3MPa高压釜中蒸汽腐蚀行为的影响。试验结果表明：铌离子注入能够改善锆-4合金抗400℃和500℃高压蒸汽腐蚀性能，并且，比较而言对500℃蒸汽腐蚀性能提高的程度更为显著。为了理解铌离子注入影响的机理，应用SEM、XRD、XPS等分析手段分析了氧化膜的形貌、相结构、注入元素的价态及组成。
本文研究了铌离子注入对锆-4合金在400℃和500℃、10．3MPa高压釜中蒸汽腐蚀行为的影响。试验结果表明：铌离子注入能够改善锆-4合金抗400℃和500℃高压蒸汽腐蚀性能，并且，比较而言对500℃蒸汽腐蚀性能提高的程度更为显著。为了理解铌离子注入影响的机理，应用SEM、XRD、XPS等分析手段分析了氧化膜的形貌、相结构、注入元素的价态及组成。
2006, 35(1):39-42.
Abstract:
Void growth behavior plays an important role in the deformation, damage and rupture of the nickel-base single crystal superalloys at high temperature. A set of creep, fatigue and thermal-mechanical-fatigue (TMF) experiments was carried out. The SEM observation on the fractured surfaces shows that for all experiments studied in this paper the fracture surfaces are made up of small facets. In the center of the facet, there is at least one void. The dimension of the void is dependent on the loading conditions. Crystallographic finite element method was applied to simulate the void growth by a cell model. Creep loading condition and plastic loading condition were modeled. The influence of the crystallographic orientations on the void growth was studied. The finite element study of the void growth can help to understand the experimental results.
Void growth behavior plays an important role in the deformation, damage and rupture of the nickel-base single crystal superalloys at high temperature. A set of creep, fatigue and thermal-mechanical-fatigue (TMF) experiments was carried out. The SEM observation on the fractured surfaces shows that for all experiments studied in this paper the fracture surfaces are made up of small facets. In the center of the facet, there is at least one void. The dimension of the void is dependent on the loading conditions. Crystallographic finite element method was applied to simulate the void growth by a cell model. Creep loading condition and plastic loading condition were modeled. The influence of the crystallographic orientations on the void growth was studied. The finite element study of the void growth can help to understand the experimental results.
12 Numerical Simulation on Thermal Shock Damage Behavior of TiB2-Cu Composite via Combustion Synthesis
2006, 35(1):47-51.
Abstract:
The thermal shock behavior of TiB2- Cu composite by combustion synthesis was investigated using plasma arc heating and numerical simulation. The transient temperalure field and thermal stress fields affected by inhomogeneous boundary conditions of heat transfer in high temperature were simulated and analyzed based on the thermal physical data with ANSYS commercial software. The results reveal that the maximum compression stresses are generated at center of sample and decreased along radius. The compression stresses transform to tensile stresses when the arc beam gets across the heating area, and the largest tensile stress takes place in the edge of the specimen. The crack may initiate in the edge of the sample, and then properly propagates to the position of center in the direction of radius. The experiment of plasma arc heating also favor and approve the rationality nf theoretical model.
The thermal shock behavior of TiB2- Cu composite by combustion synthesis was investigated using plasma arc heating and numerical simulation. The transient temperalure field and thermal stress fields affected by inhomogeneous boundary conditions of heat transfer in high temperature were simulated and analyzed based on the thermal physical data with ANSYS commercial software. The results reveal that the maximum compression stresses are generated at center of sample and decreased along radius. The compression stresses transform to tensile stresses when the arc beam gets across the heating area, and the largest tensile stress takes place in the edge of the specimen. The crack may initiate in the edge of the sample, and then properly propagates to the position of center in the direction of radius. The experiment of plasma arc heating also favor and approve the rationality nf theoretical model.
2006, 35(1):52-54.
Abstract:
以高纯蒸馏Gd为原料制备了Gd5ShGe2合金，研究了不同热处理工艺对合金的显微组织结构及磁热效应的影响。利用扫描电子显微镜及电子能谱对合金的显微组织结构及成分进行了测试。利用振动样品磁强计测量了合金在250K～290K范围内的等温磁化曲线，并根据麦克斯韦方程对其磁熵变进行了计算。研究发现，通过适当的热处理，合金的显微组织得到充分地均匀化，合金中的杂质相得到有效去除。因此，磁熵值较铸态提高将近200％，磁有序温度下降约lOK。
以高纯蒸馏Gd为原料制备了Gd5ShGe2合金，研究了不同热处理工艺对合金的显微组织结构及磁热效应的影响。利用扫描电子显微镜及电子能谱对合金的显微组织结构及成分进行了测试。利用振动样品磁强计测量了合金在250K～290K范围内的等温磁化曲线，并根据麦克斯韦方程对其磁熵变进行了计算。研究发现，通过适当的热处理，合金的显微组织得到充分地均匀化，合金中的杂质相得到有效去除。因此，磁熵值较铸态提高将近200％，磁有序温度下降约lOK。
2006, 35(1):55-58.
Abstract:
将Zn粉末置于流量为500ml／min的NH3气流中，在600℃氮化120min，制备出高质量的Zn3N2粉末。X射线衍射（XRD）表明Zn3N2粉末具有立方结构，其晶格常数为0．9788nm。扫描电子显微镜（SEM）和透射电子显微镜（TEM）观察发现Zn3N2粉末晶粒形状具有多样性。X射线光电子谱（XPS）表明Zn3N2的化学键状态与ZnO及金属Zn明显不同，表明N-Zn键的形成。用计算机模拟了Zn3N2晶体的立体结构，用高分辨电子显微镜（HRTEM）观察了Zn3N2粉末的内部结构，观察结果与Partin等提出的Zn3N2结构模型相符合。
将Zn粉末置于流量为500ml／min的NH3气流中，在600℃氮化120min，制备出高质量的Zn3N2粉末。X射线衍射（XRD）表明Zn3N2粉末具有立方结构，其晶格常数为0．9788nm。扫描电子显微镜（SEM）和透射电子显微镜（TEM）观察发现Zn3N2粉末晶粒形状具有多样性。X射线光电子谱（XPS）表明Zn3N2的化学键状态与ZnO及金属Zn明显不同，表明N-Zn键的形成。用计算机模拟了Zn3N2晶体的立体结构，用高分辨电子显微镜（HRTEM）观察了Zn3N2粉末的内部结构，观察结果与Partin等提出的Zn3N2结构模型相符合。
2006, 35(1):59-61.
Abstract:
In this paper, Nd:GGG single crystal was grown by Cz method. Fluorescence spectra and absorption spectra was measured after the Nd:GGG single crystal was cut and polished. The main absorption peak of Nd:GGG crystal is 808 nm and fluorescence-emission peak is 9430 cm-1, which correspond to 4F3/2-4I11/2 emission band of Nd3+ ions. At the same time, absorption intensity become stronger with the increasing of Nd3+ ions concentration.
In this paper, Nd:GGG single crystal was grown by Cz method. Fluorescence spectra and absorption spectra was measured after the Nd:GGG single crystal was cut and polished. The main absorption peak of Nd:GGG crystal is 808 nm and fluorescence-emission peak is 9430 cm-1, which correspond to 4F3/2-4I11/2 emission band of Nd3+ ions. At the same time, absorption intensity become stronger with the increasing of Nd3+ ions concentration.
2006, 35(1):62-65.
Abstract:
Wear resistant TieNi3Si reinforced intermetallic coatings were fabricated on a substrate of titanium alloy BT9 by laser cladding using Ti-50Ni-10Si alloy powders as the precursor materials. Results indicate that the laser clad intermetallic comings have a rapidly solidified homogeneous microstructure consisting of TieNi3Si primary dendrites and TieNi3Si/NiTi eutectic. Wear resistance of the laser clad Ti2Ni3Si reinforced intermetallic coatings was evaluated under dry sliding wear test conditions at room temperature. Because of the high hardness and strong covalent dominant atomic bonds of the Ti2Ni3Si primary dendrites with MgZn2 type Laves crystal structure and the high yield strength and toughness of the eutectic, the Ti2Ni3Si/NiTi intermetallic coatings have excellent wear resistance under dry sliding wear test conditions.
Wear resistant TieNi3Si reinforced intermetallic coatings were fabricated on a substrate of titanium alloy BT9 by laser cladding using Ti-50Ni-10Si alloy powders as the precursor materials. Results indicate that the laser clad intermetallic comings have a rapidly solidified homogeneous microstructure consisting of TieNi3Si primary dendrites and TieNi3Si/NiTi eutectic. Wear resistance of the laser clad Ti2Ni3Si reinforced intermetallic coatings was evaluated under dry sliding wear test conditions at room temperature. Because of the high hardness and strong covalent dominant atomic bonds of the Ti2Ni3Si primary dendrites with MgZn2 type Laves crystal structure and the high yield strength and toughness of the eutectic, the Ti2Ni3Si/NiTi intermetallic coatings have excellent wear resistance under dry sliding wear test conditions.
2006, 35(1):66-69.
Abstract:
The Zr41.25Ti13.75Cu12.5Ni10Be22.5 bulk metallic glass is reinforced with up to 60 volume percent of tungsten particulate. Samples with 10mm in diameter are obtained when quenching melt contained in stainless steel tube into saturated brine. A characterization based on X-ray diffraction and scanning electron microscopy is presented. Compressive tests were performed for the metallic glass matrix composites and single phase bulk metallic glass. Compressive strain-to-failure increase significantly compared to unreinforced single phase Zr41.25Ti13.75Cu12.5Ni10Be22.5 bulk metallic glass. The results are discussed in term of particulate size and yield strength of the reinforcement.
The Zr41.25Ti13.75Cu12.5Ni10Be22.5 bulk metallic glass is reinforced with up to 60 volume percent of tungsten particulate. Samples with 10mm in diameter are obtained when quenching melt contained in stainless steel tube into saturated brine. A characterization based on X-ray diffraction and scanning electron microscopy is presented. Compressive tests were performed for the metallic glass matrix composites and single phase bulk metallic glass. Compressive strain-to-failure increase significantly compared to unreinforced single phase Zr41.25Ti13.75Cu12.5Ni10Be22.5 bulk metallic glass. The results are discussed in term of particulate size and yield strength of the reinforcement.
2006, 35(1):70-73.
Abstract:
采用叠层加压SPS烧结法制备致密的YG10/YG20梯度结构硬质合金。通过调整WC粒度和添加微量元素B来调整烧结温度,使含钴量低的粉末与含钴量高的粉末的烧结温度相近。研究了烧结温度对致密度、组织形貌、显微硬度和断裂韧性的影响,分析了沿梯度截面上C,Co,W等成分、显微硬度的变化及YG10/YG20界面的结合情况。结果表明:原始WC粒度为1μm的YG10+0.05%B混合粉末和9μm的YG20混合粉末都能在1100℃~1160℃烧结致密,相对密度达到99%以上,晶粒尺寸均匀,梯度界面结合良好,没有开裂现象。低钴端的硬度达到了15500MPa~16000MPa,高钴端的硬度为11100MPa;在294N载荷的作用下低钴端的断裂韧性为12.62MPa·m1/2,而高钴端在这一载荷的作用下没有出现裂纹,断裂韧性较高,从而实现了硬质合金一端具有高硬度,另一端具有良好的韧性的有机结合。
采用叠层加压SPS烧结法制备致密的YG10/YG20梯度结构硬质合金。通过调整WC粒度和添加微量元素B来调整烧结温度,使含钴量低的粉末与含钴量高的粉末的烧结温度相近。研究了烧结温度对致密度、组织形貌、显微硬度和断裂韧性的影响,分析了沿梯度截面上C,Co,W等成分、显微硬度的变化及YG10/YG20界面的结合情况。结果表明:原始WC粒度为1μm的YG10+0.05%B混合粉末和9μm的YG20混合粉末都能在1100℃~1160℃烧结致密,相对密度达到99%以上,晶粒尺寸均匀,梯度界面结合良好,没有开裂现象。低钴端的硬度达到了15500MPa~16000MPa,高钴端的硬度为11100MPa;在294N载荷的作用下低钴端的断裂韧性为12.62MPa·m1/2,而高钴端在这一载荷的作用下没有出现裂纹,断裂韧性较高,从而实现了硬质合金一端具有高硬度,另一端具有良好的韧性的有机结合。
2006, 35(1):74-77.
Abstract:
将传统蜡基粘结剂和油＋蜡改进粘结剂体系分别与粒度为1．97μm的WC-8Co硬质合金粉末混合采用注射成形法制备了全致密高强度的硬质合金。研究了注射坯在Hz中的热脱脂工艺和溶剂脱脂与其后补充热脱脂工艺，和不同脱脂工艺对脱脂坯碳含量的影响。结果表明：油＋蜡改进粘结剂体系具有更好的热脱脂和溶剂脱脂行为。通过工艺优化和碳含量控制，在真空气氛下1400℃烧结80min制备出高抗弯强度的全致密硬质合金烧结制品。
将传统蜡基粘结剂和油＋蜡改进粘结剂体系分别与粒度为1．97μm的WC-8Co硬质合金粉末混合采用注射成形法制备了全致密高强度的硬质合金。研究了注射坯在Hz中的热脱脂工艺和溶剂脱脂与其后补充热脱脂工艺，和不同脱脂工艺对脱脂坯碳含量的影响。结果表明：油＋蜡改进粘结剂体系具有更好的热脱脂和溶剂脱脂行为。通过工艺优化和碳含量控制，在真空气氛下1400℃烧结80min制备出高抗弯强度的全致密硬质合金烧结制品。
2006, 35(1):78-81.
Abstract:
借助XRD，DSC，TEM等分析手段，研究了Fe86Zr5Nb6B3快淬带球磨粉末的热稳定性以及高压烧结条件对块体合金的相组成和晶粒尺寸的影响。结果表明：（1）球磨快淬粉末仍为非晶态，其晶化温度约510℃，该晶化过程的表观激活能庐219．5kJ／mol：（2）在5．5GPa，3min烧结条件下，当Pw=1150W后，获得了相对密度为99．1％，单相α-Fe纳米晶（20．6rim）块体合金：（3）在5．5GPa，1150W烧结条件下，当t延长至25min后，α-Fe相纳米晶粒尺寸长大到28.7nm；（4）在5．5GPa，1150W，5min烧结条件下，纳米晶块体合金的饱和磁感应强度Bs=1．26T，矫顽力Hc=4．27kA．m^-1。
借助XRD，DSC，TEM等分析手段，研究了Fe86Zr5Nb6B3快淬带球磨粉末的热稳定性以及高压烧结条件对块体合金的相组成和晶粒尺寸的影响。结果表明：（1）球磨快淬粉末仍为非晶态，其晶化温度约510℃，该晶化过程的表观激活能庐219．5kJ／mol：（2）在5．5GPa，3min烧结条件下，当Pw=1150W后，获得了相对密度为99．1％，单相α-Fe纳米晶（20．6rim）块体合金：（3）在5．5GPa，1150W烧结条件下，当t延长至25min后，α-Fe相纳米晶粒尺寸长大到28.7nm；（4）在5．5GPa，1150W，5min烧结条件下，纳米晶块体合金的饱和磁感应强度Bs=1．26T，矫顽力Hc=4．27kA．m^-1。
2006, 35(1):82-84.
Abstract:
利用熔体快淬法制备了La1-xNdxFe11．5Si1．5（x=0，0．3，0.5）快淬带。通过X射线衍射和振动样品磁强计测试了回火态（1000℃，5h）La1-xNdxFe11．5Si1．5）快淬带的相组成和磁性能。结果表明：不同成分快淬带回火后均可得到稳定的NaZnl，型化合物。和常规的熔炼法相比，用熔体快淬法通过短时间的回火（1000℃，5h）可以制成具有大磁熵变的NaZn13型的化合物。用Nd替代部分的La后，居里温度略有提高，同时保持有大的磁熵变｜△S｜；并且随着Nd含量的增加，有效制冷温区有变宽的趋势。
利用熔体快淬法制备了La1-xNdxFe11．5Si1．5（x=0，0．3，0.5）快淬带。通过X射线衍射和振动样品磁强计测试了回火态（1000℃，5h）La1-xNdxFe11．5Si1．5）快淬带的相组成和磁性能。结果表明：不同成分快淬带回火后均可得到稳定的NaZnl，型化合物。和常规的熔炼法相比，用熔体快淬法通过短时间的回火（1000℃，5h）可以制成具有大磁熵变的NaZn13型的化合物。用Nd替代部分的La后，居里温度略有提高，同时保持有大的磁熵变｜△S｜；并且随着Nd含量的增加，有效制冷温区有变宽的趋势。
2006, 35(1):85-88.
Abstract:
利用γ射线辐照制备出均匀分布在PAM中的银粒子，直径约10nm。制备出的复合物再通过物理混合的方法与EVA复合，得到稳定的纳米Ag／PAM／EVA复合材料。结果表明：纳米银复合材料具有较高的电阻率和击穿场强，较低的tgδ和较高的介电常数。这种纳米粒子的新颖特性可以用库仑阻塞机理解释。
利用γ射线辐照制备出均匀分布在PAM中的银粒子，直径约10nm。制备出的复合物再通过物理混合的方法与EVA复合，得到稳定的纳米Ag／PAM／EVA复合材料。结果表明：纳米银复合材料具有较高的电阻率和击穿场强，较低的tgδ和较高的介电常数。这种纳米粒子的新颖特性可以用库仑阻塞机理解释。
2006, 35(1):89-91.
Abstract:
In normal temperature and pressure, two kinds of one-dimensional nano-structures with different patterns and structures, whose substrate were Cu-Zn-Al alloy, were successfully prepared after treating by mixed acid. It is found that the products are similar to nanotube because of their hollow and cylindrical structures, but their tube wall is thicker and their inner diameter is thinner than that of typical nanotube. The selected area electron diffraction and EDX analyze is confirm that the products are one-dimensional Cu-Zn-Al alloy nano-structures. The growth mechanics of nano-structures are primarily studied and the growth model is also put forward.
In normal temperature and pressure, two kinds of one-dimensional nano-structures with different patterns and structures, whose substrate were Cu-Zn-Al alloy, were successfully prepared after treating by mixed acid. It is found that the products are similar to nanotube because of their hollow and cylindrical structures, but their tube wall is thicker and their inner diameter is thinner than that of typical nanotube. The selected area electron diffraction and EDX analyze is confirm that the products are one-dimensional Cu-Zn-Al alloy nano-structures. The growth mechanics of nano-structures are primarily studied and the growth model is also put forward.
2006, 35(1):92-95.
Abstract:
TiO2光催化纳米薄膜在400℃～80℃温内恒温退火1h-2h，以消除膜内非晶，提高薄膜光催化活性。热处理前后试样的检测结果表明：退火使TiO2薄膜内非晶晶化，晶粒长大，光响应电流增大。随退火温度的升高，TiO2薄膜出现由非晶斗锐钛矿斗金红石的转变。其中，600℃退火1h的TiO2薄膜为锐钛矿加金红石的混晶结构，光电流密度最大Iuv=41．2A／m^2，光催化活性最好。
TiO2光催化纳米薄膜在400℃～80℃温内恒温退火1h-2h，以消除膜内非晶，提高薄膜光催化活性。热处理前后试样的检测结果表明：退火使TiO2薄膜内非晶晶化，晶粒长大，光响应电流增大。随退火温度的升高，TiO2薄膜出现由非晶斗锐钛矿斗金红石的转变。其中，600℃退火1h的TiO2薄膜为锐钛矿加金红石的混晶结构，光电流密度最大Iuv=41．2A／m^2，光催化活性最好。
2006, 35(1):96-99.
Abstract:
In this paper, two knitting structures are designed and tested. It is observed that the resistance of Stainless Steel (SS) fiber fabric has a linear relationship with strain within a definite range. Any change in fabric structure may cause changes of the linear range and sensitivity of the strain sensor. The main mechanism of the fabric sensitive to strain has been deduced to be the change of contact resistance between yarns during stretching.
In this paper, two knitting structures are designed and tested. It is observed that the resistance of Stainless Steel (SS) fiber fabric has a linear relationship with strain within a definite range. Any change in fabric structure may cause changes of the linear range and sensitivity of the strain sensor. The main mechanism of the fabric sensitive to strain has been deduced to be the change of contact resistance between yarns during stretching.
2006, 35(1):100-104.
Abstract:
The elevated temperature plastic deformation was studied by thermomechanical processes for three kinds of Mg-RE alloys in different temperature and different strain rate. The results show that the flow stress of 1# alloy containing Ce is lower than that of 2# alloy containing Nd, and 3# alloy containing Nd and Y at same temperature and same strain rate. The 1# alloy containing Ce is more suitable for extrusion forming from thermal deformation angle.
The elevated temperature plastic deformation was studied by thermomechanical processes for three kinds of Mg-RE alloys in different temperature and different strain rate. The results show that the flow stress of 1# alloy containing Ce is lower than that of 2# alloy containing Nd, and 3# alloy containing Nd and Y at same temperature and same strain rate. The 1# alloy containing Ce is more suitable for extrusion forming from thermal deformation angle.
2006, 35(1):105-109.
Abstract:
以铸造CoCrMoC合金（ASTMF 75-82）为研究对象，通过金相观察，XRD，SEM和EDX分析以及磨损试验，研究了该合金在不同热处理条件下的显微结构与耐磨损性能。结果表明：不含C的CoCrMo合金的耐磨损性能几乎不受热处理制度的影响：含C的CoCrMoC合金在1100℃以上温度固溶处理耐磨损性能明显提高，其中1200℃是最佳温度，固溶后时效处理降低合金的耐磨损性能。分析认为，固溶引起的fcc钴基体固溶强化和适当的碳化物分布是提高耐磨损性能的主要原因，而时效引起的基体fcc相→hcp相的等温马氏体相变对耐磨损性能影响不大。
以铸造CoCrMoC合金（ASTMF 75-82）为研究对象，通过金相观察，XRD，SEM和EDX分析以及磨损试验，研究了该合金在不同热处理条件下的显微结构与耐磨损性能。结果表明：不含C的CoCrMo合金的耐磨损性能几乎不受热处理制度的影响：含C的CoCrMoC合金在1100℃以上温度固溶处理耐磨损性能明显提高，其中1200℃是最佳温度，固溶后时效处理降低合金的耐磨损性能。分析认为，固溶引起的fcc钴基体固溶强化和适当的碳化物分布是提高耐磨损性能的主要原因，而时效引起的基体fcc相→hcp相的等温马氏体相变对耐磨损性能影响不大。
2006, 35(1):114-118.
Abstract:
采用溶胶凝胶自蔓延法制备了不同配比的SiO2-CaO-P2O5-MgO系生物活性玻璃粉，并通过压制烧结工艺制成块状玻璃陶瓷材料。研究了材料的组织结构、力学性能和在骨内种植试验中的生物学行为。结果表明：经过1100℃烧结热处理后，凝胶玻璃基体中析出（Ca，Mg）3（PO4）2晶体和MgSiO3晶体，其中，硅含量较高的样品中析出晶体的尺寸较大，具有较高的弯曲强度和断裂韧性值，分别可达172MPa和2．02MPa．m^1/2。两种材料植入动物体内后与骨组织接触良好，未见明显的炎症反应。其中硅含量较高的样品植入骨内仅3周即可在骨与材料接触面处生成大量新生血管和骨小梁，植入6周后即与骨融合，两者之间钙磷含量较高且连续，没有明显的界面，这些结果证明该材料具有良好的骨组织相容性，是一种较为理想的骨修复替代材料。
采用溶胶凝胶自蔓延法制备了不同配比的SiO2-CaO-P2O5-MgO系生物活性玻璃粉，并通过压制烧结工艺制成块状玻璃陶瓷材料。研究了材料的组织结构、力学性能和在骨内种植试验中的生物学行为。结果表明：经过1100℃烧结热处理后，凝胶玻璃基体中析出（Ca，Mg）3（PO4）2晶体和MgSiO3晶体，其中，硅含量较高的样品中析出晶体的尺寸较大，具有较高的弯曲强度和断裂韧性值，分别可达172MPa和2．02MPa．m^1/2。两种材料植入动物体内后与骨组织接触良好，未见明显的炎症反应。其中硅含量较高的样品植入骨内仅3周即可在骨与材料接触面处生成大量新生血管和骨小梁，植入6周后即与骨融合，两者之间钙磷含量较高且连续，没有明显的界面，这些结果证明该材料具有良好的骨组织相容性，是一种较为理想的骨修复替代材料。
2006, 35(1):119-122.
Abstract:
为了制备均匀致密、结合强度较高的电泳陶瓷涂层,用正丁醇作分散介质,在Ti基底上电泳沉积HA/Ti复合涂层。研究了Ti基底处理、烧结温度控制以及悬浮液配方等因素对涂层结合强度的影响。用扫描电镜(SEM)对热处理后涂层形貌和结构进行观察,采用红外光谱仪(FTIR)、X射线衍射仪(XRD)、差示扫描量热仪(DSC/TG)对涂层的组成和热稳定性进行了表征。结果表明:用H2O2/NH3·H2O处理Ti基底,700℃下烧结,Ti含量为44.6%的HA/Ti复合涂层结合强度可达到23.2MPa。
为了制备均匀致密、结合强度较高的电泳陶瓷涂层,用正丁醇作分散介质,在Ti基底上电泳沉积HA/Ti复合涂层。研究了Ti基底处理、烧结温度控制以及悬浮液配方等因素对涂层结合强度的影响。用扫描电镜(SEM)对热处理后涂层形貌和结构进行观察,采用红外光谱仪(FTIR)、X射线衍射仪(XRD)、差示扫描量热仪(DSC/TG)对涂层的组成和热稳定性进行了表征。结果表明:用H2O2/NH3·H2O处理Ti基底,700℃下烧结,Ti含量为44.6%的HA/Ti复合涂层结合强度可达到23.2MPa。
2006, 35(1):123-126.
Abstract:
采用MoSi2粉末自烧结方法，在SiC电热元件表面制备一层致密的MoSi2高温抗氧化涂层，并对其高温抗氧化性进行测试。抗氧化试验在空气中1500℃炉温下进行118h和32次热循环，结果表明，带有MoSi2涂层的试样表面致密光洁，且试样抗氧化性能随MoSi2涂层厚度增加。SEM和EPMA显微分析表明，MoSi2涂层与SiC基体结合较好，没有起层和剥落，涂层中Mo分布均匀，损失约为20％。
采用MoSi2粉末自烧结方法，在SiC电热元件表面制备一层致密的MoSi2高温抗氧化涂层，并对其高温抗氧化性进行测试。抗氧化试验在空气中1500℃炉温下进行118h和32次热循环，结果表明，带有MoSi2涂层的试样表面致密光洁，且试样抗氧化性能随MoSi2涂层厚度增加。SEM和EPMA显微分析表明，MoSi2涂层与SiC基体结合较好，没有起层和剥落，涂层中Mo分布均匀，损失约为20％。
2006, 35(1):127-130.
Abstract:
The effect of BN content on sintering properties of Ni-based abradable seal alloy was investigated. The sintering process and model with BN and without BN were studied. To establish model to research the process of Ni-Cr/BN sintering expansion. BN powders hinder sintering between powders, and the sintering expansion and the density falling are discovered.
The effect of BN content on sintering properties of Ni-based abradable seal alloy was investigated. The sintering process and model with BN and without BN were studied. To establish model to research the process of Ni-Cr/BN sintering expansion. BN powders hinder sintering between powders, and the sintering expansion and the density falling are discovered.
2006, 35(1):131-133.
Abstract:
以固态氧化物为原料，采用传统方法制备错掺杂PZT压电陶瓷。通过XPS，XRD以及SEM方法分析组成为Pb1-1．5xPbZr0．54Ti0．46O3（x=0．02～0．08）压电陶瓷的元素价态，相组成以及显微结构。结果发现：合成温度900℃，可以得到钙钛矿结构。在镨掺杂为3mol％的准同型相界附近三方相和四方相并存，综合性能达最佳值：E33^T／ε0=2000，d33=418pC/N，Kp=52．9％，Qm=75。随着镨掺杂量的增加，Pr-PZT陶瓷的居里温度降低。
以固态氧化物为原料，采用传统方法制备错掺杂PZT压电陶瓷。通过XPS，XRD以及SEM方法分析组成为Pb1-1．5xPbZr0．54Ti0．46O3（x=0．02～0．08）压电陶瓷的元素价态，相组成以及显微结构。结果发现：合成温度900℃，可以得到钙钛矿结构。在镨掺杂为3mol％的准同型相界附近三方相和四方相并存，综合性能达最佳值：E33^T／ε0=2000，d33=418pC/N，Kp=52．9％，Qm=75。随着镨掺杂量的增加，Pr-PZT陶瓷的居里温度降低。
2006, 35(1):134-137.
Abstract:
采用陶瓷先驱体有机聚合物聚硅氧烷连接反应烧结碳化硅（RBSiC）陶瓷。研究了连接温度、连接压力、保温时间对连接强度的影响。通过正交优选实验，确定了最佳工艺参数：连接温度为1300℃，连接压力为25kPa，保温时间为120min。在此工艺条件下制备的连接件经3次浸渍／裂解增强处理，其抗弯强度达132．6MPa，连接件断口表面粘有大量从母材剥离下来的SiC。XRD研究表明，在1100℃～1400℃的试验范围之内，随着连接温度的逐步升高，聚硅氧烷的裂解产物发生了由非晶态向晶态的转变。这种转变对连接强度有显著影响。扫描电镜（SEM）及能谱（EDX）分析显示，连接层厚度为3μm左右，结构较为均匀致密，且与母材间界面结合良好。
采用陶瓷先驱体有机聚合物聚硅氧烷连接反应烧结碳化硅（RBSiC）陶瓷。研究了连接温度、连接压力、保温时间对连接强度的影响。通过正交优选实验，确定了最佳工艺参数：连接温度为1300℃，连接压力为25kPa，保温时间为120min。在此工艺条件下制备的连接件经3次浸渍／裂解增强处理，其抗弯强度达132．6MPa，连接件断口表面粘有大量从母材剥离下来的SiC。XRD研究表明，在1100℃～1400℃的试验范围之内，随着连接温度的逐步升高，聚硅氧烷的裂解产物发生了由非晶态向晶态的转变。这种转变对连接强度有显著影响。扫描电镜（SEM）及能谱（EDX）分析显示，连接层厚度为3μm左右，结构较为均匀致密，且与母材间界面结合良好。
2006, 35(1):138-141.
Abstract:
Indium tin oxide films(In2O3-SnO2)were deposited onto glass at different oxygen flows by R.F. magnetron sputtering method. Transmittance in visible light and an energy band gap were measured by ultraviolet spectrophotometer . square resistance was measured by four-point probe. The thickness and complex refractive index of films were measured by spectroscopic ellipsomtry. The component of the ITO films was studied by XPS. The study indicates that the deposited ratio and refractive indexes of films are related to the O2 flow rate, The transmittance in visible light is beyond 80% (including glass substrate) with the film thickness 60nm and 9sccm oxygen flux. The transmittance and square resistance can be improved by hot treatment. XPS investigation shows that the photoelectricity properties can be deteriorated by the sub-oxides, which can be reduced by oxygen flux.
Indium tin oxide films(In2O3-SnO2)were deposited onto glass at different oxygen flows by R.F. magnetron sputtering method. Transmittance in visible light and an energy band gap were measured by ultraviolet spectrophotometer . square resistance was measured by four-point probe. The thickness and complex refractive index of films were measured by spectroscopic ellipsomtry. The component of the ITO films was studied by XPS. The study indicates that the deposited ratio and refractive indexes of films are related to the O2 flow rate, The transmittance in visible light is beyond 80% (including glass substrate) with the film thickness 60nm and 9sccm oxygen flux. The transmittance and square resistance can be improved by hot treatment. XPS investigation shows that the photoelectricity properties can be deteriorated by the sub-oxides, which can be reduced by oxygen flux.
2006, 35(1):142-145.
Abstract:
制备了摩尔比为1：1的TiO2和CeO2陶瓷靶材。采用射频磁控溅射法在O2和Ar比例为5：95的混合气体中制备了玻璃基TiO2-CeO2薄膜。溅射过程中，工作气压保持在1．8Pa不变，玻璃基片温度从室温（RT）～220℃之间变化。用x射线衍射（XRD）、X射线光电子能谱（XPS）、扫描电镜（SEM）、透射电镜（TEM）和紫外-可见光谱仪研究了薄膜的物相结构、表面组成、表面形貌和镀膜试样的紫外-可见光透过率。结果表明，薄膜表面结构平滑、致密，呈微小晶粒结构，薄膜中Ti和Ce仅以Ti^4＋和Ce^4＋的形式存在；随着基片温度升高，薄膜中的细小晶粒略有长大；TiO2-CeO2镀膜玻璃可以有效地截止紫外线。
制备了摩尔比为1：1的TiO2和CeO2陶瓷靶材。采用射频磁控溅射法在O2和Ar比例为5：95的混合气体中制备了玻璃基TiO2-CeO2薄膜。溅射过程中，工作气压保持在1．8Pa不变，玻璃基片温度从室温（RT）～220℃之间变化。用x射线衍射（XRD）、X射线光电子能谱（XPS）、扫描电镜（SEM）、透射电镜（TEM）和紫外-可见光谱仪研究了薄膜的物相结构、表面组成、表面形貌和镀膜试样的紫外-可见光透过率。结果表明，薄膜表面结构平滑、致密，呈微小晶粒结构，薄膜中Ti和Ce仅以Ti^4＋和Ce^4＋的形式存在；随着基片温度升高，薄膜中的细小晶粒略有长大；TiO2-CeO2镀膜玻璃可以有效地截止紫外线。
2006, 35(1):146-149.
Abstract:
Zeolites Y and the Y(m) modified by methyltrimethoxysilane were used for the hosts to prepare the Cd-Y and Cd-Y(m) samples by ion-exchange method and then the Y-CdS and Y(m)-CdS host-guest nanocomposite samples were prepared by a hydrothermal method by using thiacetamide as a sulfur source instead of toxic hydrogen sulfide. By mean of powder X-ray diffraction, chemical analysis, infrared spectroscopy, solid diffusion reflectance absorption spectroscopy, luminescence investigation, the prepared samples were characterized. The results of powder XRD analyses show that after the incorparation of CdS into the Y and Y(m) zeolites the frameworks of the prepared samples still exist and keep high ordered property. The IR results show that the formation of a new bond Si-O-Cd in Y-CdS and Y(m)-CdS samples. The results of solid diffusion reflectance absorption spectra show that there is no absorption from Y and Y(modified) zeolites, and there is not obvious difference for the absorption spectra between the Y-CdS and Y(m)-CdS samples. Luminescence studies show that for the Y-CdS and Y(m)-CdS samples there appear luminescence. The host-guest nanocomposite materials prepared have the potential ability as luminescent materials.
Zeolites Y and the Y(m) modified by methyltrimethoxysilane were used for the hosts to prepare the Cd-Y and Cd-Y(m) samples by ion-exchange method and then the Y-CdS and Y(m)-CdS host-guest nanocomposite samples were prepared by a hydrothermal method by using thiacetamide as a sulfur source instead of toxic hydrogen sulfide. By mean of powder X-ray diffraction, chemical analysis, infrared spectroscopy, solid diffusion reflectance absorption spectroscopy, luminescence investigation, the prepared samples were characterized. The results of powder XRD analyses show that after the incorparation of CdS into the Y and Y(m) zeolites the frameworks of the prepared samples still exist and keep high ordered property. The IR results show that the formation of a new bond Si-O-Cd in Y-CdS and Y(m)-CdS samples. The results of solid diffusion reflectance absorption spectra show that there is no absorption from Y and Y(modified) zeolites, and there is not obvious difference for the absorption spectra between the Y-CdS and Y(m)-CdS samples. Luminescence studies show that for the Y-CdS and Y(m)-CdS samples there appear luminescence. The host-guest nanocomposite materials prepared have the potential ability as luminescent materials.
2006, 35(1):154-157.
Abstract:
应用传统的浆料发泡法，通过孔隙优化，成功制备出力学性能与骨匹配的多孔钛。扫描电镜分析发现其孔隙相互连通成三维网状结构；经碱热处理的多孔钛在模拟体液中浸泡14d后，表面被一层类骨磷灰石覆盖，具有良好的生物活性。此多孔钛有望成为理想的负重骨缺损修复材料。
应用传统的浆料发泡法，通过孔隙优化，成功制备出力学性能与骨匹配的多孔钛。扫描电镜分析发现其孔隙相互连通成三维网状结构；经碱热处理的多孔钛在模拟体液中浸泡14d后，表面被一层类骨磷灰石覆盖，具有良好的生物活性。此多孔钛有望成为理想的负重骨缺损修复材料。
2006, 35(1):158-160.
Abstract:
Cu64Zr36 amorphous ribbons were prepared by melting-spun technique. The crystallization process and kinetics were investigated by isothermal annealing at different temperature, DSC and XRD. The results show that the crystallization process is that Cu10Zr7 would precipitates primarily, then CuZr2. The activation energies of glass transition and crystallization are 433.7 kJ/mol and 603 kJ/mol, respectively.
Cu64Zr36 amorphous ribbons were prepared by melting-spun technique. The crystallization process and kinetics were investigated by isothermal annealing at different temperature, DSC and XRD. The results show that the crystallization process is that Cu10Zr7 would precipitates primarily, then CuZr2. The activation energies of glass transition and crystallization are 433.7 kJ/mol and 603 kJ/mol, respectively.
2006, 35(1):161-163.
Abstract:
Ag-coated Au composite nanoparticles are prepared via solution-phase reduction method and clearly observed by TEM. The optical absorption spectra show that the as-prepared particles have two distinct plasma a absorption bands. One absorption peak centers near the plasma a absorption band of pure Ag nanoparticles, another absorption peak intervenes between the plasma a absorption bands of pure Ag and pure Au nanoparticles and undergoes blue-shift. According to the experimental analysis and numerical calculation based on Mie scattering theory, it is reasonable to attribute the blue-shift to the thickness increasing of Ag-shells.
Ag-coated Au composite nanoparticles are prepared via solution-phase reduction method and clearly observed by TEM. The optical absorption spectra show that the as-prepared particles have two distinct plasma a absorption bands. One absorption peak centers near the plasma a absorption band of pure Ag nanoparticles, another absorption peak intervenes between the plasma a absorption bands of pure Ag and pure Au nanoparticles and undergoes blue-shift. According to the experimental analysis and numerical calculation based on Mie scattering theory, it is reasonable to attribute the blue-shift to the thickness increasing of Ag-shells.
2006, 35(1):164-168.
Abstract:
The progress of interracial reaction diffusion of SiC fiber-reinforced Ti matrix composites is described. The reaction diffusion models, the dynamics and thermodynamics, the control mechanism of interracial reaction, and the effect of diffusion barriers on interracial reaction diffusion are introduced. Further research directions and focus of SiC fiber reinforced Ti matrix composites are pointed out.
The progress of interracial reaction diffusion of SiC fiber-reinforced Ti matrix composites is described. The reaction diffusion models, the dynamics and thermodynamics, the control mechanism of interracial reaction, and the effect of diffusion barriers on interracial reaction diffusion are introduced. Further research directions and focus of SiC fiber reinforced Ti matrix composites are pointed out.
