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Microstructural evolution and precipitation behavior of Al-7Si-3Cu alloy prepared under 5 GPa

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Journal of Materials Science & Technology 2023年第28期159卷 138-150页

作者： Ning Fang Chunming Zou zunjie wei Hongwei Wang Jiahan Chen Zongyue Jin Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology150001 HarbinChina

This paper presents a systematic investigation of the microstructural evolution and mechanical proper-ties of Al-7Si-3Cu alloys prepared under high pressure of 5 *** is found that the dendritic structure disappears due to the enhanced stability of the growth interface under high ***,a con-siderable solute-induced modification effect is achieved in the eutectic ***,unconventional larger eutectic colonies and ultrafine nanocrystalline eutectics are observed within the intragranular ***-bined with detailed microstructural characterization,the crucial role of high pressure on the evolution of these isolated phases is *** study also explores the precipitation behavior and strengthening mechanisms of alloys prepared under direct aging and solution-aging *** the direct aging treatment,θ’phases,coarse Al 2 Cu particles,and Si particles form simultaneously in the matrix owing to the increased solid solubility of alloying elements,which results in the highest mechanical properties with a microhardness of 132.8 HV and compressive stress of 715 ***-aging treatment leads to the segregation of Si onθ’phases,which proved to be energetically favorable according to first-principles *** work provides new insights into the microstructural optimization of aluminum-silicon-based alloys through high-pressure manipulation and paves the way for further industrial applications.

关键词： Al-Si-Cu alloy High pressure Nanocrystalline eutectics Precipitates Mechanical properties

Effect of returns on microstructure and mechanical properties of Al-Cu based alloys

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China Foundry 2010年第1期7卷 37-42页

作者： Li Min Wang Hongwei wei zunjie Zhu Zhaojun School of Materials Science and Engineering Harbin Institute of Technology Harbin China

It is well known that maximal utilization of the returns can be beneficial for cost reduction,preservation of natural resources and protection of the environment,by making them into recycled Al-Cu *** this study,the influences of returns on the microstructure and mechanical properties of Al-Cu alloys have been investigated by means of optical microscopy and scanning electron *** results showed that the returns could be used to produce recycled Al-Cu alloys with fine and uniform microstructure and excellent mechanical properties,including ultimate tensile strength,yield strength and *** was found that the maximum performance of the recycled Al-Cu alloy in their properties could be achievable when the returns content was 20wt.%,which gave 219 MPa,87.16 MPa and 12.15% at as-cast state,and 525 MPa,445.3 MPa and 14.14% after heat treated,in their tensile strengths,yield strengths and elongations,*** values were much higher than those of primary alloy.

关键词： Al-Cu alloy returns microstructure mechanical properties

Valence electronic structure of tantalum carbide and nitride

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Science China(Physics,Mechanics & Astronomy) 2007年第6期50卷 737-741页

作者： FAN ChangZeng SUN LiLing wei zunjie MA MingZhen LIU RiPing ZENG SongYan WANG WenKui Department of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China National Laboratory for Superconductivity Institute of PhysicsChinese Academy of SciencesBeijing 100080China National Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQin-huangdao 066004China

The valence electronic structures of tantalum carbide (TaC) and tantalum nitride (TaN) are studied by using the empirical electronic theory (EET). The results reveal that the bonds of these compounds have covalent,metallic and ionic characters. For a quantitative analysis of the relative strength of these components,their ionicities have been calculated by implanting the results of EET to the PVL model. It has been found that the ionicity of tantalum carbide is smaller than that of tantalum nitride. The EET results also reveal that the covalent electronic number of the strongest bond in the former is larger than that of the latter. All these suggest that the covalent bond of TaC is stronger than that of TaN,which coincides to that de-duced from the first-principles method.

关键词： TaC TaN valence electronic structure ionicity

Fabrication,structure and compression performance of Inconel 617 superalloy honeycomb

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Rare Metals 2007年第S1期26卷 199-204页

作者： WANG Hongwei,wei zunjie,ZHU Zhaojun,and LI Zhiwei School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

Inconel 617 metal honeycombs with designed porosity,cell size and cell morphology were fabricated using fused deposition modelling rapid prototype *** microstructure and compression properties of Inconel 617 metal honeycomb were *** results indicate that Inconel 617 metal honeycomb structure can be fabricated using fused deposition modelling technique,the processes are simple and the size of honeycomb is *** sintered Inconel 617 honeycombs consist of matrix,γ phase,and grain boundary precipitates,Cr7C3 and M23C6 type *** honeycomb microstructure sintered using fine powder particles are denser than that of coarse powder *** strength and Young’s modulus increase with the relative density of honeycomb *** the influence of the relative density on Young’s modulus is greater than that of yield strength.

关键词： rapid prototype fused deposition modelling metal honeycomb compression properties

Microstructure and compressive properties of INCO-617 alloy hollow sphere foam

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Rare Metals 2007年第S1期26卷 129-133页

作者： LI Zhiwei,wei zunjie,WANG Hongwei,and ZHU Zhaojun School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

INCO-617 alloy hollow sphere foams with average aperture of about 3 mm and about 0.12 mm wall thickness were fabricated by hollow sphere *** the wet spheres,which are formed as powder shells from slurry by coating polystyrene balls,were arranged with body-centered cubic(BCC) ***,the sphere stacks were heat-treated in vacuum at 350 ℃ for 40 min to decompose the organic materials,and sintered at different temperatures for different *** effects of slurry components,sintering temperature and sintering time on the density and porosity of cell wall of hollow sphere foam were studied through Scanning Electron *** results show that the densities of INCO-617 alloy hollow sphere foam,increasing with the increase of powder content in slurry,sintering temperature and sintering time,range from 1.112 to 1.216 g·*** of sintering time can reduce the porosity of cell wall,which enhances the compression strength of hollow sphere foam significantly.

关键词： hollow sphere metallic foam INCO-617 alloy compression

Non-equilibrium microstructure and the metastable phase of Al-9.6wt%Mg Alloy solidification under high pressure

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Rare Metals 2007年第S1期26卷 231-236页

作者： wei zunjie,WANG Zhenling,WANG Hongwei,ZHU Zhaojun,CAO Lei,and LI Zhiwei School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The non-equilibrium microstructure and a new metastable phase of Al-9.6wt%Mg alloy solidified at 6 GPa were studied by optical microscope,differential scanning calorimetry,X-ray diffraction and transmission electron *** results showed that dendrite microstructure was refined,and the solid solubility of Mg in α-Al phase increased ***,the lattice parameter of α-Al phase ***3Mg2 phases disappeared under high pressure *** particular,a metastable phase with small size(20 nm or so) was produced in the alloy,its melting temperature range was 464～518.2 ℃,which was higher than that of Al3Mg2 phase(453～465 ℃) under normal *** metastable phases located in the interdendritic *** was the first time that the metastable phase was found in Al-Mg alloy at a high pressure of 6 *** formation mechanism of the metastable phases was discussed.

关键词： high pressure solidification microstructure metastable phase Al-9.6wt%Mg alloy

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Al含量对Nb-Ti-C合金组织的影响

稀有金属材料与工程 2011年第8期40卷 1458-1461页

作者：魏文庆王宏伟邹鹑鸣魏尊杰哈尔滨工业大学黑龙江哈尔滨150001

利用真空非自耗电弧炉制备了不同Al含量的Nb-21Ti-4C(βNb-Ti)合金,研究了Al元素含量变化对Nb-21Ti-4C合金组织和晶格常数的影响。研究表明:铸态条件下合金由枝晶生长的Nb基固溶体(Nbss),碳化物((Nb,Ti)C),Nb3Al和枝晶间Nbss/MC共晶组... 详细信息

利用真空非自耗电弧炉制备了不同Al含量的Nb-21Ti-4C(βNb-Ti)合金,研究了Al元素含量变化对Nb-21Ti-4C合金组织和晶格常数的影响。研究表明:铸态条件下合金由枝晶生长的Nb基固溶体(Nbss),碳化物((Nb,Ti)C),Nb3Al和枝晶间Nbss/MC共晶组织构成;Al元素部分固溶进入Nbss和MC中,随着Al含量增加,以Nb3Al相生长在Nbss内部。Al元素含量增加,使得Nbss枝晶先变大后变小。1100℃,24h热处理后,Nbss内部析出针状或片状碳化物和Nb3Al,导致Nbss晶格常数增大;枝晶间碳化物内部Nbss进一步长大,Nb原子的析出和Al元素固溶含量变化导致碳化物晶格常数改变。

关键词： βNb-Ti合金 (Nb,Ti)C Nb3Al 晶格常数

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Al-20Mg合金高压凝固力学性能研究

金属学报 2014年第8期50卷 971-978页

作者：接金川邹鹑鸣王宏伟魏尊杰哈尔滨工业大学材料科学与工程学院金属精密热加工国家级重点实验室哈尔滨115110 大连理工大学材料科学与工程学院大连116024

将Al-20Mg合金在不同压力下凝固,采用OM,XRD以及拉伸实验对合金凝固后的物相组织及力学性能进行研究.结果表明,随着凝固压力的升高,Mg元素在Al基体中的固溶度提高,当凝固压力为2 GPa时,Al-20Mg合金转变成为过饱和固溶体,其力学性能显著... 详细信息

将Al-20Mg合金在不同压力下凝固,采用OM,XRD以及拉伸实验对合金凝固后的物相组织及力学性能进行研究.结果表明,随着凝固压力的升高,Mg元素在Al基体中的固溶度提高,当凝固压力为2 GPa时,Al-20Mg合金转变成为过饱和固溶体,其力学性能显著提高,合金的抗拉强度提高到474.8 MPa,是常压凝固之后合金抗拉强度的8.9倍,屈服强度达到232.8 MPa,延伸率也达到11.1%.当凝固压力增加到3 GPa时,合金的屈服强度有所下降,这是由于更高压力下凝固后Mg在固溶体中的均匀分布会降低合金的力学性能.高压凝固后Al-20Mg合金的断裂机制由常压下的解理断裂转变为高压下的韧性断裂.

关键词： Al-Mg合金高压凝固固溶体力学性能断裂机制

合金元素对电弧熔炼TiC/Ti-6Al-4V复合材料中TiC生长形态的影响

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稀有金属材料与工程 2010年第10期39卷 1773-1776页

作者：曹磊王宏伟邹鹑鸣魏尊杰 Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

采用非自耗电弧熔炼制备含不同微合金元素的10vol%TiC/Ti-6Al-4V复合材料,研究不同的微量合金元素对复合材料中TiC形态的影响。结果表明,原始铸态复合材料中TiC形态主要是粗大且发达的枝晶状。而基体中加入0.3%(质量分数,下同)的Sn元素... 详细信息

采用非自耗电弧熔炼制备含不同微合金元素的10vol%TiC/Ti-6Al-4V复合材料,研究不同的微量合金元素对复合材料中TiC形态的影响。结果表明,原始铸态复合材料中TiC形态主要是粗大且发达的枝晶状。而基体中加入0.3%(质量分数,下同)的Sn元素后,TiC生长被抑制,TiC形态变为细小分散的颗粒状;0.3%的Ni被加入后,增大了TiC的结晶区间,使TiC枝晶生长变得更加发达;而0.3%的Nb元素的加入,则减小了TiC的结晶区间,从而减少了初晶TiC数量,促进了共晶TiC的形成。

关键词：微合金元素元素对电弧熔炼复合材料 TiC 生长形态 Composites 结晶区间质量分数枝晶生长原始铸态微量合金颗粒状制备抑制晶状结果基体共晶分散