Volume 0,Issue 2,2001 Table of Contents
2001(2).
Abstract:
The ablation properties of ZrCp/W composite were measured using a self--made oxyacetylene ablation equipment. The results indicate that the values of mass ablation rate and linear ablation rate are in the order of W>30vol%ZrCp/W>40vol% ZrCp/W. The ablation resistance of the composites greatly increases with increasing ZrC particle content. The important ablation surface temperature curves were detected in situ using a multi--wavelength pyrometer. Thermochemical oxidation of ZrC and W is the main ablation mechanism of ZrCp/W composites.
The ablation properties of ZrCp/W composite were measured using a self--made oxyacetylene ablation equipment. The results indicate that the values of mass ablation rate and linear ablation rate are in the order of W>30vol%ZrCp/W>40vol% ZrCp/W. The ablation resistance of the composites greatly increases with increasing ZrC particle content. The important ablation surface temperature curves were detected in situ using a multi--wavelength pyrometer. Thermochemical oxidation of ZrC and W is the main ablation mechanism of ZrCp/W composites.
2 Microstructures of Heat-Treated L2_1/L1_2 Multi-Phase Intermetallic Alloys in the System Co-Ni-Al-Ti
2001(2).
Abstract:
Various heat-treatments has been carried out for high-temperature structural intermetallic alloys comprised of L21-type (Co,Ni)2AlTi and L12,-type (Co, Ni)3 (Al,Ti) ordered phases in the quaternary system Co-Ni-Al-Ti. The optimum heat- treatment parameters were found out through microstructural analysis, and the properties of the intermetallic alloy have been improved.
Various heat-treatments has been carried out for high-temperature structural intermetallic alloys comprised of L21-type (Co,Ni)2AlTi and L12,-type (Co, Ni)3 (Al,Ti) ordered phases in the quaternary system Co-Ni-Al-Ti. The optimum heat- treatment parameters were found out through microstructural analysis, and the properties of the intermetallic alloy have been improved.
2001(2).
Abstract:
介绍了一套液氮温区入（Ｂ，Ｔ）测量系统，该系统用增大液氮的饱和蒸气压来达到提高液氮温度的目的。用该系统研究了磁场和温度（测量范围分别为０．１Ｔ～０．８Ｔ和７７Ｋ～９０Ｋ）对Ｂｉ－２２２３／Ａｇ多芯带材（１９芯和３７芯）临界电流的影响。
介绍了一套液氮温区入（Ｂ，Ｔ）测量系统，该系统用增大液氮的饱和蒸气压来达到提高液氮温度的目的。用该系统研究了磁场和温度（测量范围分别为０．１Ｔ～０．８Ｔ和７７Ｋ～９０Ｋ）对Ｂｉ－２２２３／Ａｇ多芯带材（１９芯和３７芯）临界电流的影响。
2001(2).
Abstract:
研究了四元混合稀土（Ｌａ_ｘＣｅ_(１－ｘ)）０．９（ＰｒＮｄ）０．１（ＮｉＣｏＭｎＡｌ）_５（ｘ＝０．４～０．９）贮氢合金中Ｌａ， Ｃｅ的不同含量和比例对合金结构和电化学性能的影响。结果表明：合金晶胞的ａ轴和晶胞体积随Ｌａ含量ｘ的增加而增大，而 ｃ 轴则在小幅度内波动；合金电极的最大放电容量随 ｘ的增加而增大，并在 ｘ＝０． ９０时达到最大值（３２８． ９ ｍＡｈ／ｇ），但平均每循环容量衰减率提高，充放电循环稳定性下降。
研究了四元混合稀土（Ｌａ_ｘＣｅ_(１－ｘ)）０．９（ＰｒＮｄ）０．１（ＮｉＣｏＭｎＡｌ）_５（ｘ＝０．４～０．９）贮氢合金中Ｌａ， Ｃｅ的不同含量和比例对合金结构和电化学性能的影响。结果表明：合金晶胞的ａ轴和晶胞体积随Ｌａ含量ｘ的增加而增大，而 ｃ 轴则在小幅度内波动；合金电极的最大放电容量随 ｘ的增加而增大，并在 ｘ＝０． ９０时达到最大值（３２８． ９ ｍＡｈ／ｇ），但平均每循环容量衰减率提高，充放电循环稳定性下降。
2001(2).
Abstract:
The relationships of wall stress of hydrogen storage bed with cycle index of hydrogen ab-/desorption, capacity of hydrogen storage, packing fraction, and thickness of the wall of hydrogen storage bed have been studied using strain gauge. The experimental results indicate that the wall stress increases with increasing packing fraction and the thickness of the wall. The wall stress slowly increases as amount of hydrogen storage reaches a certain value.
The relationships of wall stress of hydrogen storage bed with cycle index of hydrogen ab-/desorption, capacity of hydrogen storage, packing fraction, and thickness of the wall of hydrogen storage bed have been studied using strain gauge. The experimental results indicate that the wall stress increases with increasing packing fraction and the thickness of the wall. The wall stress slowly increases as amount of hydrogen storage reaches a certain value.
2001(2):81-84.
Abstract:
关于Zr-2和Zr-4合金的转折机理有多种假说。其中相变假说认为：锆合金的氧化速度主要受氧化物/金属界面附近t-ZrO2向m-ZrO2转变的控制。在400℃，10.3MPa过热蒸汽中，相变是由应力松驰引起的，在300℃的LiOH水溶液中，OH∧-1与氧空位的相互作用促使t-ZrO2向m-ZrO2转变。本文着重讨论了相变假说及其相变机理，最后提出了自己的观点，氧化膜中压压力达到一定值时，以有Li∧ 进入氧化膜使其力学性能恶化可能导致氧化膜的碎裂，由此引起腐蚀加速和出现转折。
关于Zr-2和Zr-4合金的转折机理有多种假说。其中相变假说认为：锆合金的氧化速度主要受氧化物/金属界面附近t-ZrO2向m-ZrO2转变的控制。在400℃，10.3MPa过热蒸汽中，相变是由应力松驰引起的，在300℃的LiOH水溶液中，OH∧-1与氧空位的相互作用促使t-ZrO2向m-ZrO2转变。本文着重讨论了相变假说及其相变机理，最后提出了自己的观点，氧化膜中压压力达到一定值时，以有Li∧ 进入氧化膜使其力学性能恶化可能导致氧化膜的碎裂，由此引起腐蚀加速和出现转折。
2001(2):85-88.
Abstract:
用预处理熔铸工艺制备的TiC颗粒增强钛基复合材料的室温和300℃～700℃拉伸性能测量表明：复合材料相应于未复合基体合金的强度增量在温室达到24%，而到650℃降为4%，表明复合材料的显微组织有利于室温和低于650℃中的等温度强化；400℃～500℃时出现动态变时效，但延性并未明显下降，意味着PTMP工艺制成的TiC/Ti复合材料间隙元素含量低；300℃～500℃下加工硬化明显增加，可能与复合体中位错密度度增加有关。
用预处理熔铸工艺制备的TiC颗粒增强钛基复合材料的室温和300℃～700℃拉伸性能测量表明：复合材料相应于未复合基体合金的强度增量在温室达到24%，而到650℃降为4%，表明复合材料的显微组织有利于室温和低于650℃中的等温度强化；400℃～500℃时出现动态变时效，但延性并未明显下降，意味着PTMP工艺制成的TiC/Ti复合材料间隙元素含量低；300℃～500℃下加工硬化明显增加，可能与复合体中位错密度度增加有关。
2001(2):89-92.
Abstract:
A molecular dynamics simulation is carried out for a 50 000-atom system to study the variation of microstructural configuration of liquid metal Al during a rapid cooling process. The transition mechanism is identified by various bond-types and cluster structures. A very clear picture of how metal atoms form clusters and how they evolve further has been obtained, which will give us an important enlightenment to understand the forming mechanism and microscopic process of an amorphous structure.
A molecular dynamics simulation is carried out for a 50 000-atom system to study the variation of microstructural configuration of liquid metal Al during a rapid cooling process. The transition mechanism is identified by various bond-types and cluster structures. A very clear picture of how metal atoms form clusters and how they evolve further has been obtained, which will give us an important enlightenment to understand the forming mechanism and microscopic process of an amorphous structure.
2001(2):93-96.
Abstract:
采用电化学测试技术对TiNiCu形状记忆合金在Hank's人工模拟体液中的耐蚀性进行了研究。结果表明，TiNiCu合金阳极极化时，在100mV～150mV电位区间出现了低电位活性溶解。pH值的降低和Cl∧-1浓度的升高，使孔蚀电位Eb值负移，孔蚀敏感性增大。在Hank's人工模拟体液中TiNiCu合金的耐蚀性比TiNiCu形状记忆合金劣，其原因是TiNiCu合金的晶体结构不单一，造成电化学性质不均一，同时晶界富Ti2Ni析出和疏松状态的Cu的表面富集，促进阳极溶解。
采用电化学测试技术对TiNiCu形状记忆合金在Hank's人工模拟体液中的耐蚀性进行了研究。结果表明，TiNiCu合金阳极极化时，在100mV～150mV电位区间出现了低电位活性溶解。pH值的降低和Cl∧-1浓度的升高，使孔蚀电位Eb值负移，孔蚀敏感性增大。在Hank's人工模拟体液中TiNiCu合金的耐蚀性比TiNiCu形状记忆合金劣，其原因是TiNiCu合金的晶体结构不单一，造成电化学性质不均一，同时晶界富Ti2Ni析出和疏松状态的Cu的表面富集，促进阳极溶解。
2001(2):97-100.
Abstract:
A novel PEG--based binder for metal injection molding (MIM) has been studied. The novel binder is made of high- density polyethylene (HDPE), polyethylene glycol (PEG), polymer W, stearic acid(SA) and dioctyl phthalate (DOP). The binder has strong adhesive to Fe-2Ni powder and high solid loading, and could easily mix with powders to obtain a homogeneous feedstock. The feedstock exhibits good molding behavior. The feedstock possesses pseudo plasticity and exhibits good rheological properties. The binder could easily be removed in a short time in ethanol without defects, and environmental concern associated with other solvents are avoided.
A novel PEG--based binder for metal injection molding (MIM) has been studied. The novel binder is made of high- density polyethylene (HDPE), polyethylene glycol (PEG), polymer W, stearic acid(SA) and dioctyl phthalate (DOP). The binder has strong adhesive to Fe-2Ni powder and high solid loading, and could easily mix with powders to obtain a homogeneous feedstock. The feedstock exhibits good molding behavior. The feedstock possesses pseudo plasticity and exhibits good rheological properties. The binder could easily be removed in a short time in ethanol without defects, and environmental concern associated with other solvents are avoided.
2001(2):101-104.
Abstract:
用自制的氧乙炔烧蚀装置对ZrCp/W复合材料烧蚀性能进行了研究。结果表明复合材料的质量烧蚀率和线烧蚀率由低到高的排列顺序为40％ZrCp(体积分数,下同)/W＜30％ZrCp/W＜W；钨中加入ZrC颗粒明显提高了钨的抗烧蚀性能,而且ZrC颗粒含量越高,材料抗烧蚀性能越好。并用多波长高温计对烧蚀表面温度进行在线测试。复合材料烧蚀机理是W,ZrC的氧化烧蚀。
用自制的氧乙炔烧蚀装置对ZrCp/W复合材料烧蚀性能进行了研究。结果表明复合材料的质量烧蚀率和线烧蚀率由低到高的排列顺序为40％ZrCp(体积分数,下同)/W＜30％ZrCp/W＜W；钨中加入ZrC颗粒明显提高了钨的抗烧蚀性能,而且ZrC颗粒含量越高,材料抗烧蚀性能越好。并用多波长高温计对烧蚀表面温度进行在线测试。复合材料烧蚀机理是W,ZrC的氧化烧蚀。
2001(2):105-108.
Abstract:
A series of fine duplex microstructures of TiAl-based intermetallic alloys have been obtained by various heat treatments. The residual stresses of different microstructures were evaluated using X-ray diffraction technique. It was found that the residual stresses change with the microstroctures and the volume fraction of a2 phase.
A series of fine duplex microstructures of TiAl-based intermetallic alloys have been obtained by various heat treatments. The residual stresses of different microstructures were evaluated using X-ray diffraction technique. It was found that the residual stresses change with the microstroctures and the volume fraction of a2 phase.
2001(2):109-113.
Abstract:
A lamellar structural unit model of PST crystal used in finite element analysis has been built on the basis of studying the microstructure of PST crystal. The calculation indicates that as crack is parallel to the lamellae, the resolved shear stresses on all slip planes ahead of crack tip are low, and the slip is difficulty, while the normal stress on lamellar interface is higher than that on other cleavage planes, which results in crack nucleation along lamellar interfaces preferentially and low ductility. As the crack perpendicular to the lamellae, the resolved stress on many slip planes ahead of crack tip is much higher, and the slip is easy. The maximum normal stress on the translamellar cleavage planes rather than the lamellar interface, which results in crack nucleation along translamellar interfaces preferentially and good ductility.
A lamellar structural unit model of PST crystal used in finite element analysis has been built on the basis of studying the microstructure of PST crystal. The calculation indicates that as crack is parallel to the lamellae, the resolved shear stresses on all slip planes ahead of crack tip are low, and the slip is difficulty, while the normal stress on lamellar interface is higher than that on other cleavage planes, which results in crack nucleation along lamellar interfaces preferentially and low ductility. As the crack perpendicular to the lamellae, the resolved stress on many slip planes ahead of crack tip is much higher, and the slip is easy. The maximum normal stress on the translamellar cleavage planes rather than the lamellar interface, which results in crack nucleation along translamellar interfaces preferentially and good ductility.
14 Microstructures of Heat-Treated L21/L12 Multi-Phase
Intermetallic Alloys in the System Co-Ni-Al-Ti
2001(2):114-117.
Abstract:
对由L21型（Co,Ni）2AlTi和L12型（Co,Ni)3（Al,Ti）两种有序相组成的Co-Ni-Al系新型金属间化合物高温结构实验用合金进行了不同制度的热处理，并对相应的显微组织特征进行了分析研究。找到了控制显微组织以优化性能的热处理参数。
对由L21型（Co,Ni）2AlTi和L12型（Co,Ni)3（Al,Ti）两种有序相组成的Co-Ni-Al系新型金属间化合物高温结构实验用合金进行了不同制度的热处理，并对相应的显微组织特征进行了分析研究。找到了控制显微组织以优化性能的热处理参数。
2001(2):118-122.
Abstract:
利用透射电子显微镜研究了层片状 γ－ＴｉＡｌ合金室温压－压循环变形中的孪生行为。结果表明：在变形后的层片组织中出现了大量的｛１１１｝〈１１２ ］型形变孪晶，这些形变孪晶对层片位向有明显的依赖性，在一些位向的片层内可大量产生，而在另一些位向的片层内却难以发现，且产生的李晶和片展边界呈一定的夹角关系；同时，在同一片层内观察到了两组切变方向相反的形变孪生类型，根据孪生切变的单向性和位向三角形 内孪生切变的Ｓｃｈｍｉｄ因子分析，发现这两组孪生类型分别为 型孪生和 型孪生；孪生切变与位错滑移有一定的互补关系，在孪生切变受阻的片层内，出现了平行于孪生切变方向的位错滑移。孪生切变的多样性和孪生与滑移的互补关系大大缓解了各向异性层片组织中的应力集中，从而有效地抑制了裂纹萌生，使 γ－ＴｉＡｌ合金循环塑变能力提高。
利用透射电子显微镜研究了层片状 γ－ＴｉＡｌ合金室温压－压循环变形中的孪生行为。结果表明：在变形后的层片组织中出现了大量的｛１１１｝〈１１２ ］型形变孪晶，这些形变孪晶对层片位向有明显的依赖性，在一些位向的片层内可大量产生，而在另一些位向的片层内却难以发现，且产生的李晶和片展边界呈一定的夹角关系；同时，在同一片层内观察到了两组切变方向相反的形变孪生类型，根据孪生切变的单向性和位向三角形 内孪生切变的Ｓｃｈｍｉｄ因子分析，发现这两组孪生类型分别为 型孪生和 型孪生；孪生切变与位错滑移有一定的互补关系，在孪生切变受阻的片层内，出现了平行于孪生切变方向的位错滑移。孪生切变的多样性和孪生与滑移的互补关系大大缓解了各向异性层片组织中的应力集中，从而有效地抑制了裂纹萌生，使 γ－ＴｉＡｌ合金循环塑变能力提高。
2001(2):123-126.
Abstract:
The crack initiation and propagation in Al2O3 seeded P/M Rene95 have been studied by SEM observation in-situ for tension loading stage of the P/M Rene95 sample. The results show that during SEM in-situ tension process, cracks initiate at ceramic inclusions. Generally, the cracks nucleate at the inclusion/matrix interface, and easily propagate along the interfaces and reach the matrix. At last, some inclusion particles may separate from the matrix and fall off.
The crack initiation and propagation in Al2O3 seeded P/M Rene95 have been studied by SEM observation in-situ for tension loading stage of the P/M Rene95 sample. The results show that during SEM in-situ tension process, cracks initiate at ceramic inclusions. Generally, the cracks nucleate at the inclusion/matrix interface, and easily propagate along the interfaces and reach the matrix. At last, some inclusion particles may separate from the matrix and fall off.
2001(2):127-130.
Abstract:
The nanocrystalline powder of W-Ni-Fe alloy used for Metal injection Molding(MIM) has been studied. The nanopowder prepared by Mechanical Alloying(MA) was mixed with a wax-based binder to form a feedstock. The effects of MA milling time, nanopowder volume fraction and temperature on the rheological behavior of the feedstock are discussed. With increase of milling time, the viscosity of the feedstock and the sensitivity of viscosity to shear strain rate decrease. Therefore, the fluidity and formalization of this powder feedstock at the condition of long time milling become better. With increase of powder volume fraction, the viscosity of the feedstock has a non-linear increase, which follows the formula: . Here n is equal to 0. 68. The change of viscosity with temperature and shear strain rate is small for the MA powder, so the quality of these MIM products is not strongly effected by the changes of temperature and injection speed.
The nanocrystalline powder of W-Ni-Fe alloy used for Metal injection Molding(MIM) has been studied. The nanopowder prepared by Mechanical Alloying(MA) was mixed with a wax-based binder to form a feedstock. The effects of MA milling time, nanopowder volume fraction and temperature on the rheological behavior of the feedstock are discussed. With increase of milling time, the viscosity of the feedstock and the sensitivity of viscosity to shear strain rate decrease. Therefore, the fluidity and formalization of this powder feedstock at the condition of long time milling become better. With increase of powder volume fraction, the viscosity of the feedstock has a non-linear increase, which follows the formula: . Here n is equal to 0. 68. The change of viscosity with temperature and shear strain rate is small for the MA powder, so the quality of these MIM products is not strongly effected by the changes of temperature and injection speed.
2001(2):131-134.
Abstract:
The effects of various surfactants on properties of the polyethylene glycol (PEG)-Polymethyl methacrylate/Fe-2Ni feedstock are studied. First, one-molecule-layer model is used to calculate theoretically amount of surfactant needed to form onemolecule-layer absorption on powders. Then, different kinds of surfactants , such as, stearic acid, span-20, span-80, tween-60 etc., are added into the binder respectively. It was found that the surfactants increase the maximum powder loading by decreasing contact angle between the binder and the powder, and viscosity of the feedstock. Even the amount of surfactant is much higher than that of one-molecule-layer absorption, the surfactant still have its effective function. The effects of different kinds of surfactants on the properties of feedstock are not the same. By selecting a proper surfactant, the maximum powder loading can reach 55% (volume fraction)for Fe-2Ni carbonyl powder and PEG--based binder.
The effects of various surfactants on properties of the polyethylene glycol (PEG)-Polymethyl methacrylate/Fe-2Ni feedstock are studied. First, one-molecule-layer model is used to calculate theoretically amount of surfactant needed to form onemolecule-layer absorption on powders. Then, different kinds of surfactants , such as, stearic acid, span-20, span-80, tween-60 etc., are added into the binder respectively. It was found that the surfactants increase the maximum powder loading by decreasing contact angle between the binder and the powder, and viscosity of the feedstock. Even the amount of surfactant is much higher than that of one-molecule-layer absorption, the surfactant still have its effective function. The effects of different kinds of surfactants on the properties of feedstock are not the same. By selecting a proper surfactant, the maximum powder loading can reach 55% (volume fraction)for Fe-2Ni carbonyl powder and PEG--based binder.
2001(2):135-137.
Abstract:
介绍了一套液氮温区Jc（B，T）测量系统，该系统用增大液氮的饱和蒸气压来达到提高液氮温度的目的。用该系统研究了磁场的温度（测量范围分别为0.1T～ 0.8T和77K～90K)对Bi-2223/Ag多芯带材（19芯和37芯）临界电流的影响。
介绍了一套液氮温区Jc（B，T）测量系统，该系统用增大液氮的饱和蒸气压来达到提高液氮温度的目的。用该系统研究了磁场的温度（测量范围分别为0.1T～ 0.8T和77K～90K)对Bi-2223/Ag多芯带材（19芯和37芯）临界电流的影响。
2001(2):138-140.
Abstract:
Inorganic (CdS, Ag ) - polyacrylamide (PAM ) nanocomposites were prepared successfully using a convenient ultraviolet irradiation technique. It was found that the inorganic nanoparticles could be well homogeneously dispersed in the polymer matrices as the result from the fact that polymerization of organic monomer and formation of inorganic nanoparticles were simultaneous. It is very interesting that the presence of inorganic ions may be favorable for the Polylnerization of organic monomer, meanwhile the organic polymer matrices can efficiently prevent producing inorganic nanoparticles from aggregation. This technique is also applied to the fabrication of other inorganic-polymer hybrid nanocomposites.
Inorganic (CdS, Ag ) - polyacrylamide (PAM ) nanocomposites were prepared successfully using a convenient ultraviolet irradiation technique. It was found that the inorganic nanoparticles could be well homogeneously dispersed in the polymer matrices as the result from the fact that polymerization of organic monomer and formation of inorganic nanoparticles were simultaneous. It is very interesting that the presence of inorganic ions may be favorable for the Polylnerization of organic monomer, meanwhile the organic polymer matrices can efficiently prevent producing inorganic nanoparticles from aggregation. This technique is also applied to the fabrication of other inorganic-polymer hybrid nanocomposites.
21 Study on Structures and Electrochemical Properties of the Alloys (LaxCe1-x)0.9(PrNd)0.1(NiCoMnAl)5
2001(2):141-144.
Abstract:
研究了四元混合稀土（LaxCe1-x)0.9(PrNd）0.1（Ni3.55Co0.75Mn0.4Al0.3）（x=0.4～0.9）贮氢合金中La，Ce的不同含量和比例对合金结构和电化学性能的影响。结果表明：合金晶胞的α轴和晶胞体积随La含量x的增加而增大，而c轴则在小幅度内波动；合金电极的最大放电容量随x的增加而增大，并在x=0.90时达到最大值（328.9mAh/g），但平均每循环容量衰减率提高，充放电循环稳定性下降。
研究了四元混合稀土（LaxCe1-x)0.9(PrNd）0.1（Ni3.55Co0.75Mn0.4Al0.3）（x=0.4～0.9）贮氢合金中La，Ce的不同含量和比例对合金结构和电化学性能的影响。结果表明：合金晶胞的α轴和晶胞体积随La含量x的增加而增大，而c轴则在小幅度内波动；合金电极的最大放电容量随x的增加而增大，并在x=0.90时达到最大值（328.9mAh/g），但平均每循环容量衰减率提高，充放电循环稳定性下降。
2001(2):145-148.
Abstract:
制备了Cu13Zn,Cu13Zn0.1Zr,Cu13Zn0.1Cr3种合金，通过力学性能测定、金相和透射电镜观察，考察了Zr，Cr对Cu13Zn合金力学性能的影响。结果发现：Zr和Cr能够提高Cu13Zn合金再结晶温度和强度，Cu13Zn0.1Zr0.1Cr合金经500℃，1h退火处理后的屈服强度和抗拉强度分别为298MPa和395MPa，延伸率达到29%，满足高速大功率异步电动机转子导条材料的力学性能要求；Zr和Cr对Cu13Zn合金的强化机制主要是亚结构强化和第二相粒子强化。
制备了Cu13Zn,Cu13Zn0.1Zr,Cu13Zn0.1Cr3种合金，通过力学性能测定、金相和透射电镜观察，考察了Zr，Cr对Cu13Zn合金力学性能的影响。结果发现：Zr和Cr能够提高Cu13Zn合金再结晶温度和强度，Cu13Zn0.1Zr0.1Cr合金经500℃，1h退火处理后的屈服强度和抗拉强度分别为298MPa和395MPa，延伸率达到29%，满足高速大功率异步电动机转子导条材料的力学性能要求；Zr和Cr对Cu13Zn合金的强化机制主要是亚结构强化和第二相粒子强化。
2001(2):149-152.
Abstract:
The effects of carbon content, moulding pressure, and carbon particle size of green body on microstructure and properties of reaction-bonded silicon carbide (RBSC) have been investigated. The experimental results show that moulding pressure should match the carbon content of green body, or else, the properties of RBSC decrease. For the green body containing a certain size of SiC powders, the carbon particle should be less than a certain size, or else, the density and fracture strength of RBSC decrease with increasing carbon particle size.
The effects of carbon content, moulding pressure, and carbon particle size of green body on microstructure and properties of reaction-bonded silicon carbide (RBSC) have been investigated. The experimental results show that moulding pressure should match the carbon content of green body, or else, the properties of RBSC decrease. For the green body containing a certain size of SiC powders, the carbon particle should be less than a certain size, or else, the density and fracture strength of RBSC decrease with increasing carbon particle size.
2001(2):153-156.
Abstract:
采用电阻应变测量法研究了LaNi5-xAlx系列合金吸放氢循环床体壁应力与循环次数、贮氢容量、壁厚以及松装比的关系。结果表明：松装比大和薄壁的贮氢床应力要大；且随吸放氢循环的进行，壁应力增大更明显；在贮氢量达到一定值后，壁应力才缓慢增大。
采用电阻应变测量法研究了LaNi5-xAlx系列合金吸放氢循环床体壁应力与循环次数、贮氢容量、壁厚以及松装比的关系。结果表明：松装比大和薄壁的贮氢床应力要大；且随吸放氢循环的进行，壁应力增大更明显；在贮氢量达到一定值后，壁应力才缓慢增大。
2001(2):157-159.
Abstract:
在工业纯铜中加入微量锂能提高其再结晶温度，试验表明：加入0.04%（质量百分数）锂，使冷拔后的工业纯铜的再结晶开始温度从400℃提高到440℃，这是由于加入锂后，固溶于铜中，造成铜的晶格畸变，对再结晶过程中的位错运动与重排起阻碍作用，抑制再结晶过程的形核和晶界迁移，从而抑制再结晶，提高铜的再结晶温度。
在工业纯铜中加入微量锂能提高其再结晶温度，试验表明：加入0.04%（质量百分数）锂，使冷拔后的工业纯铜的再结晶开始温度从400℃提高到440℃，这是由于加入锂后，固溶于铜中，造成铜的晶格畸变，对再结晶过程中的位错运动与重排起阻碍作用，抑制再结晶过程的形核和晶界迁移，从而抑制再结晶，提高铜的再结晶温度。
