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漫长的独行之路——深切怀念两年前还和我们在一起的父亲金冶
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作者 金力美 《美术》 北大核心 2008年第11期64-69,共6页
春风刮起来的时候天还很冷.地面还堆着雪.结着冰。而产稻区已无处不是一头头水牛身负重犁.辛勤耕作的情景。
关键词 金冶 画家 绘画作品 绘画艺术
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铁马秋风编史育人的金冶将军
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作者 夏继诚 《大江南北》 2022年第9期21-23,共3页
今年是原南京军区副参谋长、司令部正军职顾问金冶将军诞辰100周年。他15岁从家乡浙江温州秘密奔赴皖南参加新四军,教导大队毕业后留在军部参谋处工作,直至1953年抗美援朝战争结束,15年中一直在高级领导机关任作战参谋、科长、处长。194... 今年是原南京军区副参谋长、司令部正军职顾问金冶将军诞辰100周年。他15岁从家乡浙江温州秘密奔赴皖南参加新四军,教导大队毕业后留在军部参谋处工作,直至1953年抗美援朝战争结束,15年中一直在高级领导机关任作战参谋、科长、处长。1940年9月间,他跟随军长叶挺参加繁昌保卫战,后又在陈毅、粟裕、谭震林、许世友、宋时轮等首长身边参赞戎机,参加了抗日战争、解放战争、抗美援朝战争中的许多战役战斗。 展开更多
关键词 许世友 正军职 抗美援朝战争 宋时轮 副参谋长 浙江温州 金冶 南京军区
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Removal of boron from metallurgical grade silicon by electromagnetic induction slag melting 被引量:12
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作者 罗大伟 刘宁 +2 位作者 卢一平 张国良 李廷举 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1178-1184,共7页
A new purification process was developed to remove impurities in metallurgical grade silicon (MG-Si) by electromagnetic induction slag melting (EISM). Vacuum melting furnace was used to purify boron in different s... A new purification process was developed to remove impurities in metallurgical grade silicon (MG-Si) by electromagnetic induction slag melting (EISM). Vacuum melting furnace was used to purify boron in different slag systems. The results show that the removal effect in SiO2-CaO-Al2O3 systems is better than that in other slag systems by EISM. The boron content in MG-Si is successfully reduced from 1.5× 10^-5 to 0.2× 10^-5 during EISM at 1 823 K for 2 h. Meanwhile, Al, Ca and Mg elements in MG-Si are also well removed and their removal efficiencies reach 85.0%, 50.2% and 66.7%, respectively, which indicates that EISM is very effective to remove boron and metal impurities in silicon. 展开更多
关键词 metallurgical grade silicon slag system partition ratio
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Removal of phosphorus from metallurgical grade silicon by Ar-H_2O gas mixtures 被引量:7
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作者 李峰 邢鹏飞 +2 位作者 李大纲 庄艳歆 涂赣峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3470-3475,共6页
The removal of phosphorus in metallurgical grade silicon (MG-Si) by water vapor carried with high purity argon was examined. The effect of the nozzle types, refining time, refining temperature, refining gas temperat... The removal of phosphorus in metallurgical grade silicon (MG-Si) by water vapor carried with high purity argon was examined. The effect of the nozzle types, refining time, refining temperature, refining gas temperature and refining gas flow rate on the phosphorus removed was investigated by the self-designed gas blowing device. The optimal refining conditions are nozzle type of holes at bottom and side, refining time of 3 h, refining temperature of 1793 K, refining gas temperature of 373 K, refining gas flow rate of 2 L/min. Under these optimal conditions, the phosphorus content in MG-Si is reduced from 94×10^-6 initially to 11×10-6 (mass fraction), which indicates that gas blowing refining is very effective to remove phosphorus in MG-Si. 展开更多
关键词 metallurgical grade silicon gas blowing PHOSPHORUS THERMODYNAMICS
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Thermodynamic behavior and morphology of impurities in metallurgical grade silicon in process of O_2 blowing 被引量:7
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作者 伍继君 马文会 +3 位作者 李彦龙 杨斌 刘大春 戴永年 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期260-265,共6页
Gas blowing is a valid method to remove the impurities from metallurgical grade silicon(MG-Si) melt.The thermodynamic behavior of impurities Fe,Al,Ca,Ti,Cu,C,B and P in MG-Si was studied in the process of O2 blowing... Gas blowing is a valid method to remove the impurities from metallurgical grade silicon(MG-Si) melt.The thermodynamic behavior of impurities Fe,Al,Ca,Ti,Cu,C,B and P in MG-Si was studied in the process of O2 blowing.The removal efficiencies of impurities in MG-Si were investigated using O2 blowing in ladle.It is found that the removal efficiencies are higher than 90% for Ca and Al and nearly 50% for B and Ti.The morphology of inclusions was analyzed and the phases Al3Ni,NiSi2 and Al3Ni were confirmed in MG-Si by X-ray diffraction.It was found that SiB4 exists in Si?B binary system.The chemical composition of inclusions in MG-Si before and after refining was analyzed by SEM-EDS.It is found that the amount of white inclusion reduces for the removal of most Al and Ca in the forms of molten slag inclusion and the contents of Fe,Ni and Mn in inclusion increase for their inertia in silicon melt with O2 blowing. 展开更多
关键词 metallurgical grade silicon THERMODYNAMICS O2 blowing IMPURITIES INCLUSION removal efficiency
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Boron removal in purifying metallurgical grade silicon by CaO-SiO_2 slag refining 被引量:9
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作者 伍继君 李彦龙 +3 位作者 马文会 魏奎先 杨斌 戴永年 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1231-1236,共6页
Boron removal from metallurgical grade silicon (MG-Si) using a calcium silicate slag was studied. The results show that it is impossible basically to remove boron using a pure SiO2 refining. The oxidizing ability of... Boron removal from metallurgical grade silicon (MG-Si) using a calcium silicate slag was studied. The results show that it is impossible basically to remove boron using a pure SiO2 refining. The oxidizing ability of CaO-SiO2 slag for boron removal was characterized by establishing the thermodynamic relationship between the distribution coefficient of boron (LB) and the activities of SiO2 and CaO. The experimental results show that the distribution coefficient and the removal efficiency of boron are greatly improved with the increase of CaO proportion in the slag. The maximal value of LB reaches 1.57 with a slag composition of 60%CaO-40%SiO2 (mass fraction). The boron content in the refined silicon is reduced from 18×10^-6 to 1.8×10^-6 using slag refining at 1600 ℃ for 3 h with a CaO-SiO2/MG-Si ratio of 2.5, and the removal efficiency of boron reaches 90%. 展开更多
关键词 metallurgical grade silicon boron removal THERMODYNAMICS distribution coefficient slag refining
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Low-temperature purification process of metallurgical silicon 被引量:8
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作者 赵立新 王志 +1 位作者 郭占成 李成义 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1185-1192,共8页
The removal of B and P consumes most of heat energy in Si metallurgical purification process for solar-grade Si. Metal-liquating purification of metallurgical grade silicon (MG-Si), also called Si-recrystallization ... The removal of B and P consumes most of heat energy in Si metallurgical purification process for solar-grade Si. Metal-liquating purification of metallurgical grade silicon (MG-Si), also called Si-recrystallization from metal liquid, was a potential energy-saving method for the removal of B and P efficiently, since Si could be melted at lower temperature by alloying with metal. The selection criteria of metal-liquating system was elaborated, and Al, Sn and In were selected out as the optimum metallic mediums. For Sn-Si system, the segregation coefficient of B decreased to 0.038 at 1 500 K, which was much less than 0.8 at the melting point of Si. The mass fraction of B was diminished from 15×10^-6 to 0.1×10^-6 as MG-Si was purified by twice, while that of most metallic elements could be decreased to 0.1×10^-6 by purifying just once. During the metal-liquating process, the formation of compounds between impurity elements and Si was also an important route of impurity removal. Finally, one low-temperature metallurgical process based on metal-liquating method was proposed. 展开更多
关键词 metal liquating method metallurgical purification process tin-silicon system solar grade silicon
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Microstructure and mechanical properties of Ti-45Al-5.5(Cr,Nb,B,Ta) alloy sintered at different SPS temperatures 被引量:2
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作者 肖树龙 徐丽娟 +2 位作者 于宏宝 田竟 陈玉勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期2960-2964,共5页
TiAl alloy bulk samples with the composition of Ti-45Al-5.5(Cr,Nb,B,Ta) (mole fraction, %) were prepared by high energy mechanical milling and spark plasma sintering (SPS) and then heat treatment. The microstructure a... TiAl alloy bulk samples with the composition of Ti-45Al-5.5(Cr,Nb,B,Ta) (mole fraction, %) were prepared by high energy mechanical milling and spark plasma sintering (SPS) and then heat treatment. The microstructure and mechanical properties after heat treatment of TiAl alloy prepared by SPS at different temperatures were studied. The results showed that the morphology of high energy mechanically milled powder was irregular and the average grain size was about decades micrometers. X-ray diffraction analysis showed that the mechanically milled powder was composed of two phases of TiAl and Ti3Al. The main phase of TiAl and few phases of Ti3Al and TiB2 were observed in the SPS bulk samples of Ti-45Al-5.5(Cr,Nb,B,Ta) alloy. For samples sintered at 900 °C and 1000 °C, the microstructure was duplex structure with some fine equiaxed gamma grains and thin needly TiB2 phases. With the SPS temperature increasing from 900 °C to 1000 °C, the micro-hardness was changed little, the compression strength increased from 1812 MPa to 2275 MPa and the compression ratio increased from 22.66% to 25.59%. The fractography results showed that the compression fracture transform of the SPS Ti-45Al-5.5(Cr,Nb,B,Ta) alloy was rgranular rupture. 展开更多
关键词 TiAl alloy powder metallurgy spark plasma sintering (SPS) heat treatment
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Phase transformation and damping behavior of lightweight porous TiNiCu alloys fabricated by powder metallurgy process 被引量:2
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作者 江鸿杰 柯常波 +2 位作者 曹姗姗 马骁 张新平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2029-2036,共8页
Porous TiNiCu ternary shape memory alloys (SMAs) were successfully fabricated by powder metallurgy method. The microstructure, martensitic transformation behavior, damping performance and mechanical properties of th... Porous TiNiCu ternary shape memory alloys (SMAs) were successfully fabricated by powder metallurgy method. The microstructure, martensitic transformation behavior, damping performance and mechanical properties of the fabricated alloys were intensively studied. It is found that the apparent density of alloys decreases with increasing the Cu content, the porous Ti50Ni40Cu10 alloy exhibits wide endothermic and exothermic peaks arisen from the hysteresis of martensitic transformations, while the porous Ti50Ni30Cu20 alloy shows much stronger and narrower endothermic and exothermic peaks owing to the B2-B19 transformation taking place easily. Moreover, the porous Ti50Ni40Cu10 alloy shows a lower shape recovery rate than the porous Ti50Ni50 alloy, while the porous Ti50Ni30Cu20 alloy behaves reversely. In addition, the damping capacity (or internal friction, IF) of the porous TiNiCu alloys increases with increasing the Cu content. The porous Ti50Ni30Cu20 alloy has very high equivalent internal friction, with the maximum equivalent internal friction value five times higher than that of the porous Ti50Ni50 alloy. 展开更多
关键词 porous TiNiCu alloys powder metallurgy martensitic transformation damping behavior
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Effect of thermal annealing on defects of upgraded metallurgical grade silicon 被引量:3
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作者 吴洪军 马文会 +4 位作者 陈秀华 蒋咏 梅向阳 张聪 吴兴惠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1340-1347,共8页
Effect of thermal annealing on the upgraded metallurgical grade(UMG)-Si was investigated under different conditions.The dislocation,grain boundaries and preferred growth orientation of Si ingot were characterized by... Effect of thermal annealing on the upgraded metallurgical grade(UMG)-Si was investigated under different conditions.The dislocation,grain boundaries and preferred growth orientation of Si ingot were characterized by optical microscopy,electron back scattering diffraction(EBSD) and X-ray diffractometry(XRD),respectively.The arrange order of dislocation density of Si ingot is from the lowest in the middle to the lower in the bottom and low in the top before and after annealing.And it decreases gradually with increase of the annealing temperature.The number of small angle grain boundaries declines gradually until disappears whereas the proportion of coincidence site lattice(CSL) grain boundaries increases firstly and then decreases.The twin boundary Σ3 reaches the highest proportion of 28% after annealing at 1 200 ℃ for 3 h.Furthermore,the crystal grains in different positions gain the best preferred growth orientation,which can promote the following machining of Si ingot and the conversion efficiency of solar cells. 展开更多
关键词 upgraded metallurgical grade(UMG-Si) ANNEALING dislocation density grain boundaries
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Effects of addition of NH_4HCO_3 on pore characteristics and compressive properties of porous Ti-10%Mg composites 被引量:6
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作者 王月勤 陶杰 +1 位作者 张金龙 汪涛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1074-1079,共6页
Porous Ti-Mg composites were successfully fabricated through powder metallurgy processing with ammonium hydrogen carbonate (NH4HCO3) as a space-holder. The effects of NH4HCO3 on properties of porous composites were ... Porous Ti-Mg composites were successfully fabricated through powder metallurgy processing with ammonium hydrogen carbonate (NH4HCO3) as a space-holder. The effects of NH4HCO3 on properties of porous composites were comprehensively investigated. The pore characteristics and compressive properties of the specimens were characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results show that the porosity of the porous composites can be tailored effectively by changing the amount of NH4HCO3 added, and the use of NI-I4HCO3 has no influence on the microstructure and phase constituents of the Ti-10%Mg porous composites. The open porosity and compressive strength as well as compressive elastic modulus vary with the adding amount and particle size of NHaHCO3. When the mass fraction of NHaHCO3 added is 25%, elastic modulus and compressive strength of composites with porosity of around 50% are found to be similar to those of human bone. 展开更多
关键词 Ti-Mg composite NHaHCO3 powder metallurgy POROSITY COMPRESSIVE
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Flow behavior and processing map of PM Ti-47Al-2Cr-0.2Mo alloy 被引量:4
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作者 李慧中 曾敏 +2 位作者 梁霄鹏 李洲 刘咏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期754-760,共7页
The flow stress features of PM Ti-47Al-2Cr-0.2Mo alloy were studied by isothermal compression in the temperature range from 1000 to 1150 °C with strain rates of 0.001-1 s-1 on Gleeble-1500 thermo-simulation machi... The flow stress features of PM Ti-47Al-2Cr-0.2Mo alloy were studied by isothermal compression in the temperature range from 1000 to 1150 °C with strain rates of 0.001-1 s-1 on Gleeble-1500 thermo-simulation machine.The results show that the deformation temperature and strain rate have obvious effects on the flow characteristic,and the flow stress increases with increasing strain rate and decreasing temperature.The processing maps under different deformation conditions were established.The processing maps of this alloy are sensitive to strains.The processing map at the strain of 0.5 exhibits two suitable deformation domains of 1000-1050 °C at 0.001-0.05 s-1 and 1050-1125 °C at 0.01-0.1 s-1.The optimum parameters for hot working of the alloy are deformation temperature of 1000 °C and strain rate of 0.001 s-1 according to the processing map and microstructure at true strain of 0.5. 展开更多
关键词 powder metallurgy TiAl based alloy hot compression deformation processing map
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Hot deformation behaviors of 35% SiC_p/2024Al metal matrix composites 被引量:6
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作者 郝世明 谢敬佩 +3 位作者 王爱琴 王文焱 李继文 孙浩亮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2468-2474,共7页
The hot deformation behaviors of 35%SiCp/2024 aluminum alloy composites were studied by hot compression tests using Gleeble-1500D thermo-mechanical simulator at temperatures ranging from 350 to 500 °C under strai... The hot deformation behaviors of 35%SiCp/2024 aluminum alloy composites were studied by hot compression tests using Gleeble-1500D thermo-mechanical simulator at temperatures ranging from 350 to 500 °C under strain rates of 0.01-10 s-1. The true stress-true strain curves were obtained in the tests. Constitutive equation and processing map were established. The results show that the flow stress decreases with the increase of deformation temperature at a constant strain rate, and increases with the increase of strain rate at constant temperature, indicating that composite is a positive strain rate sensitive material. The flow stress behavior of composite during hot compression deformation can be represented by a Zener-Hollomon parameter in the hyperbolic sine form. Its activation energy for hot deformation Q is 225.4 kJ/mol. To demonstrate the potential workability, the stable zones and the instability zones in the processing map were identified and verified through micrographs. Considering processing map and microstructure, the hot deformation should be carried out at the temperature of 500 °C and the strain rate of 0.1-1 s-1. 展开更多
关键词 metal matrix composites constitutive equations processing map MICROSTRUCTURE powder metallurgy
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Predominance diagrams for Zn(Ⅱ)-NH_3-Cl^--H_2O system 被引量:3
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作者 丁治英 陈启元 +1 位作者 尹周澜 刘葵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期832-840,共9页
The thermodynamics in zinc hydrometallurgical process was studied using a chemical equilibrium modeling code(GEMS) to predict the zinc solubility and construct the species distribution and predominance diagrams for ... The thermodynamics in zinc hydrometallurgical process was studied using a chemical equilibrium modeling code(GEMS) to predict the zinc solubility and construct the species distribution and predominance diagrams for the Zn(Ⅱ)-NH3-H2O and Zn(Ⅱ)-NH3-Cl--H2O system.The zinc solubilities in ammoniacal solutions were also measured with equilibrium experiments,which agree well with the predicted values.The distribution and predominance diagrams show that ammine and hydroxyl ammine complexes are the main aqueous Zn species,Zn(NH3)24-is predominant in weak alkaline solution for both Zn(Ⅱ)-NH3-H2O and Zn(Ⅱ)-NH3-Cl--H2O systems.In Zn(Ⅱ)-NH3-Cl--H2O system,the ternary complexes containing ammonia and chloride increase the zinc solubility in neutral solution.There are three zinc compounds,Zn(OH)2,Zn(OH)1.6Cl0.4 and Zn(NH3)2Cl2,on which the zinc solubility depends,according to the total ammonia,chloride and zinc concentration.These thermodynamic diagrams show the effects of ammonia,chloride and zinc concentration on the zinc solubility,which can provide thermodynamic references for the zinc hydrometallurgy. 展开更多
关键词 THERMODYNAMICS predominance diagram zinc hydrometallurgy ammonia leaching
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Microstructures and properties of Al-50%SiC composites for electronic packaging applications 被引量:9
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作者 滕飞 余琨 +4 位作者 罗杰 房宏杰 史春丽 戴翌龙 熊汉青 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第10期2647-2652,共6页
Al?50%SiC (volume fraction) composites containing different sizesofSiC particles (average sizesof 23, 38 and 75 μm) were prepared by powder metallurgy. The influences of SiC particle sizes and annealing on the p... Al?50%SiC (volume fraction) composites containing different sizesofSiC particles (average sizesof 23, 38 and 75 μm) were prepared by powder metallurgy. The influences of SiC particle sizes and annealing on the propertiesof the compositeswere investigated. The results show that SiC particles are distributed uniformly in the Al matrix. The coarse SiC particles result in higher coefficient of thermal expansion (CTE) and higher thermal conductivity (TC), while fine SiC particles decrease CTE and improve flexural strength of the composites. The morphology and size of SiC particles in the composite are not influenced by the annealing treatment at 400℃for 6h. However, the CTE and the flexural strength of annealed composites are decreased slightly, and the TCis improved. The TC, CTE and flexural strength of the Al/SiC composite with averageSiC particlesize of75 μm are 156 W/(m·K), 11.6×10^-6K^-1 and 229 MPa, respectively. 展开更多
关键词 Al-50%SiC composites powder metallurgy thermal properties flexural strength electronic packagingmaterial
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Preparation, microstructure and dislocation of solar-grade multicrystalline silicon by directional solidification from metallurgical-grade silicon 被引量:5
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作者 苏海军 张军 +1 位作者 刘林 傅恒志 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2548-2553,共6页
A vacuum directional solidification with high temperature gradient was performed to prepare low cost solar-grade multicrystalline silicon (mc-Si) directly from metallurgical-grade mc-Si. The microstructure character... A vacuum directional solidification with high temperature gradient was performed to prepare low cost solar-grade multicrystalline silicon (mc-Si) directly from metallurgical-grade mc-Si. The microstructure characteristic, grain size, boundary, solid-liquid growth interface, and dislocation structure under different growth conditions were studied. The results show that directionally solidified multicrystalline silicon rods with high density and orientation can be obtained when the solidification rate is below 60 μm/s. The grain size gradually decreases with increasing the solidification rate. The control of obtaining planar solid-liquid interface at high temperature gradient is effective to produce well-aligned columnar grains along the solidification direction. The growth step and twin boundaries are preferred to form in the microstructure due to the faceted growth characteristic of mc-Si. The dislocation distribution is inhomogeneous within crystals and the dislocation density increases with the increase of solidification rate. Furthermore, the crystal growth behavior and dislocation formation mechanism of mc-Si were discussed. 展开更多
关键词 multi-crystalline silicon metallurgical-grade silicon silicon solar cell directional solidification MICROSTRUCTURE
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Formation and evolution of secondary minerals during bioleaching of chalcopyrite by thermoacidophilic Archaea Acidianus manzaensis 被引量:2
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作者 刘红昌 夏金兰 +5 位作者 聂珍媛 文闻 杨云 马陈燕 郑雷 赵屹东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第9期2485-2494,共10页
The formation and evolution of secondary minerals during bioleaching of chalcopyrite by thermoacidophilic Archaea Acidianus manzaensis were analyzed by combining synchrotron radiation X-ray diffraction(SR-XRD) and S... The formation and evolution of secondary minerals during bioleaching of chalcopyrite by thermoacidophilic Archaea Acidianus manzaensis were analyzed by combining synchrotron radiation X-ray diffraction(SR-XRD) and S, Fe and Cu Kα X-ray absorption near edge structure(XANES) spectroscopy. Leaching experiment showed that 82.4% of Cu2+ was dissolved by A. manzaensis after 10 d. The surface of chalcopyrite was corroded apparently and covered with leaching products. During bioleaching, the formation and evolution of secondary minerals were as follows: 1) little elemental sulfur, jarosite, bornite and chalcocite were found at days 2 and 4; and 2) bornite and chalcocite disappeared, covellite formed, and jarosite gradually became the main component at days 6 and 10. These results indicated that metal-deficiency sulfides chalcocite and bornite were first formed with a low redox potential value(360-461 m V), and then gradually transformed to covellite with a high redox potential value(461-531 m V). 展开更多
关键词 BIOLEACHING CHALCOPYRITE Acidianus manzaensis secondary minerals FORMATION EVOLUTION
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Microstructures of PM Ti-45Al-10Nb alloy fabricated by reactive sintering 被引量:1
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作者 孙宏飞 李学问 房文斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1454-1459,共6页
Powder metallurgy Ti-45Al-10 Nb alloys was successfully fabricated by reactive sintering of milled powders at 1350 °C for 2 h in vacuum. The microstructure, in particular, constituent phases, grain size, precipit... Powder metallurgy Ti-45Al-10 Nb alloys was successfully fabricated by reactive sintering of milled powders at 1350 °C for 2 h in vacuum. The microstructure, in particular, constituent phases, grain size, precipitates of the product was investigated in detail. The results indicate that a double phase γ+α2 microstructure containing Ti2 Al C precipitate is obtained under the sintering condition, and the alloy exhibits a fine and homogenous microstructure compared with traditional Ti Al base. In fine grain structure, the average grain sizes for the γ and α2 phases are(2.3±0.05) and(5.6±0.05) μm, respectively. Additionally, numerous dislocations are observed in the alloy, and the dislocation density in γ phase is significantly higher than that in α2 phase. The formation mechanisms of the dislocation in the present alloy were also discussed in detail. 展开更多
关键词 high Nb-TiAl alloy powder metallurgy microstructure DISLOCATION
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Tribological behaviors of Fe-Al-Cr-Nb alloyed layer deposited on 45 steel via double glow plasma surface metallurgy technique 被引量:2
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作者 罗西希 姚正军 +6 位作者 张平则 陈煜 杨红勤 吴小凤 张泽磊 林玉划 徐尚君 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3694-3699,共6页
Double glow plasma surface metallurgy technique was used to fabricate a Fe?Al?Cr?Nb alloyed layer onto the surface of the 45 steel. The microstructures and composition of th?eA Fl?eCr?Nb alloyed layer were analyzed by... Double glow plasma surface metallurgy technique was used to fabricate a Fe?Al?Cr?Nb alloyed layer onto the surface of the 45 steel. The microstructures and composition of th?eA Fl?eCr?Nb alloyed layer were analyzed by scanning electronic microscopy, X-ray diffraction and energy dispersive spectroscopy. The results indicate thatthe 20 μm alloyed layer is homogeneous and compact. The alloyed elements exhibit a gradient distribution along the cross section. Microhardness and nanoindentation tests imply that the surface hardness of the alloyed layer reaches HV 580, which is almost 2.8 times that of the substrate. Compared with the substrate, the alloyed layer has a much smaller displacement and a larger elastic modulus. According to the friction and wear tests at room temperature, the? FeAl?Cr?Nb alloyed layer has lower friction coefficient and less wear mass, implying that the Fe?Al?Cr?Nb alloyed layer can effectively improve the surface hardness and wear resistance of the substrate. 展开更多
关键词 Fe-Al-Cr-Nb alloyed layer double glow plasma surface metallurgy technique tribological behavior
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Effect of sintering processing on property of porous Ti using space holder technique 被引量:2
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作者 李伯琼 李志强 陆兴 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期2965-2973,共9页
Porous Ti for the application in clinic orthopaedics field was manufactured by powder metallurgy technique using polymethyl methacrylate as the space holder under different sintering conditions.The final morphological... Porous Ti for the application in clinic orthopaedics field was manufactured by powder metallurgy technique using polymethyl methacrylate as the space holder under different sintering conditions.The final morphological features and mechanical properties were described.The results show that the increase of sintering temperature and time leads to improved grain size of porous Ti ligament and decreased pore size,with a concomitant increase of tensile strength and elastic modulus.The microstructure and mechanical properties of solid Ti depend more on the sintering temperature and time than those of porous Ti.The relative contributions of these mechanisms of porous Ti vary with the initial microstructure and oxygen content. 展开更多
关键词 porous Ti powder metallurgy microstructure mechanical property
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