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Ti69NbCrZrX中间层脉冲电流促进扩散焊tial/tialNb接头的组织与性能

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材料工程 2024年

作者：吕彦龙范佳锋候金保柴禄陶军中国航空制造技术研究院航空焊接与连接技术航空科技重点实验室华南理工大学国家金属材料近净成形工程技术研究中心

以新型Ti69NbCrZrX为中间层，采用脉冲电流促进扩散焊在900 ℃/30 min/8 MPa参数下连接tial合金与Ti2AlNb合金。通过SEM，EDS，EBSD和室温拉伸技术分析焊后接头显微组织和接头性能。结果表明：以Ti69NbCrZrX为中间层可获得无缺陷tial/Ti... 详细信息

以新型Ti69NbCrZrX为中间层，采用脉冲电流促进扩散焊在900 ℃/30 min/8 MPa参数下连接tial合金与Ti2AlNb合金。通过SEM，EDS，EBSD和室温拉伸技术分析焊后接头显微组织和接头性能。结果表明：以Ti69NbCrZrX为中间层可获得无缺陷tial/Ti2AlNb接头。接头界面组织主要分为为tial扩散影响区、中间层扩散区和Ti2AlNb扩散影响区。tial扩散影响区组织由白色β相和灰色块状α2相组成，中间层扩散区组织主要由灰色块状的α2+α相和白色的β/B2相组成，Ti2AlNb扩散影响区由β/B2基体相和分布在其中的板条状和针状O相组成。接头室温拉伸强度均值为642.5 MPa，达到母材强度的91.57%。接头断裂以沿晶脆性断裂为主，穿晶脆性断裂为辅。

关键词： tial Ti AlNb 脉冲电流促进扩散焊中间层

MICROSTRUCTURES OF tial BASED ALLOYS PREPARED BY HOT PRESSING ELEMENTAL POWDERS

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中国有色金属学会会刊：英文版 1998年第3期8卷 42-47页

作者： Yong, Liu Baiyun, Huang Yuehui, He Bing, Wang Central South Univ of Technology Changsha China

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关键词： tial based alloy hot press powder metallurgy

Microstructure and mechanical properties of tial/tial joints brazed with a newly developed Ti–Ni–Nb–Zr quaternary filler alloy

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Progress in Natural Science:Materials International 2022年第6期32卷 758-768页

作者： H.S.Ren Y.L.Shang X.Y.Ren Y.J.Jing H.P.Xiong Y.Y.Cheng Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials

A novel Ti-Ni-Nb-Zr quaternary filler alloy with the composition of Ti-(19～25)Ni-(15～25)(Nb+Zr)(wt.%) was *** filler alloy was composed of(Ti,Nb)ss,(Ti,Zr,Nb)ss+(Ti,Zr)2Ni,α-Ti and Ti2Ni *** was fabricated into filler foil with a thickness of about 45 μm by a rapid solidification *** results indicate that the liquidus temperature of the Ti-Ni-Nb-Zr brazing alloy was about 978℃,and the brazing alloy presented excellent wettability on tial *** tial joint mainly consisted of β/B2 phase,Ti2Al,Ti2AlNi and α2-Ti3Al *** diffusion of Al atom from base metal to brazed seam led to the formation of Ti2Al and *** that no previously references on XRD pattern of Ti2AlNi compound can be found,Ti2AlNi cast alloy specimen was specially prepared and XRD peaks were specially *** micro-hardness and bending strength tests of the Ti2AlNi phase were carried out,and the results were 761 HV and 192 MPa,*** brazing parameters of 1010 ℃/10 min offered the joint shear strength of 280 MPa at room temperature,and the joints exhibited tensile strength of 372 MPa at room temperature and 340 MPa at 750 ℃,indicating that the newly developed filler alloy could offer a stable high-temperature strength.

关键词： tial Brazing Filler alloy Microstructure Mechanical properties

Effect of the formation process of transient liquid phase (TLP) on the interface structure of tial joints

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Journal of University of Science and Technology Beijing 2005年第5期12卷 431-435页

作者： Huiping Duan Jun Luo Karl-Heinz Bohm Mustafa Kogak School of Materials Science and Technology Beijing University of Aeronautics and Astronautics Beijing 100083 China Institute for Materials Research GKSS Research Center Geesthacht 21502 Germany

tial has been joined employing the transient liquid phase （TLP） bonding with Ti combined with Cu, Ni or Fe foils. Experimental results showed that though the interface structures of the joints are quite different, all the joined zones are composed of five sublayers, i.e. two diffusion zones, two interfacial zones and an interlayer. It has been convinced that the formation process of the transient liquid phase controls the diffusion behavior of melting point depressant （MPD） Cu, Ni, and Fe atoms, which leads to form different interface structures of the joints.

关键词： tial transient liquid phase (TLP) bonding interface

Role of boron in tial alloy development: a review

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Rare Metals 2016年第1期35卷 1-14页

作者： Dawei Hu Interdisciplinary Research Centre in Materials University of Birmingham

Boron was found to be a unique grain refiner in cast tial alloys in the beginning of 1990 s and has become an element in most of the tial alloys developed to *** the past 25 or so years,efforts to understand the role of boron in solidification,solid-phase transformation,thermal and thermomechanical processing and mechanical properties of tial alloys and the relevant mechanisms never *** a result,abundant knowledge on boron in tial alloys has been accumulated but scattered in various research papers and conference *** review summarises the progress in understanding boron and its impacts on the tial alloy systems.

关键词： Titanium aluminide tial Ti3Al Boron Grain refinement

Morphology of discontinuous coarsening in fully lamellar tial

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中国有色金属学会会刊：英文版 2000年第1期10卷 10-13页

作者：唐建成黄伯云贺跃辉谢鲲中南工业大学粉末冶金国家重点实验室湖南长沙

The morphology of discontinuous coarsening in Ti 48Al 2Cr(mole fraction, %) was investigated. Three types of morphology were observed in tial specimens heat treated at temperatures ranging from 950 ℃ to 1 250 ℃. Type Ⅰ has straight coarsened secondary lamellae nearly parallel to the colony boundary, and it forms along the colony boundaries nearly normal to the primary lamellae. Type Ⅱ has straight coarsened secondary lamellae nearly normal to the colony boundary. Type Ⅲ consists of curved secondary lamellae that have no distinct orientation with the colony boundary and the primary lamellae. At the same time, the effect of temperature and the orientation between the lamellae and the colony boundaries on the morphology was analyzed.

关键词： tial based alloy discontinuous coarsening morphology

Dislocation self-interaction in tial:Evolution of super-dislocation dipoles revealed by atomistic simulations

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Journal of Materials Science & Technology 2021年第10期69卷 138-147页

作者： Z.Zhen H.Wang C.Y.Teng C.G.Bai D.S.Xu R.Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of China.Shenyang 110016China School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Laboratory of Fundamental Research AVIC China Aero-Polytechnology EstablishmentBeijing 100028.China

As one of the fundamental outcomes of dislocation self-interaction,dislocation dipoles have an important influence on the plastic deformation of materials,especially on fatigue and *** this work,superdislocation dipoles inγ-tial andα_(2)-Ti_(3)Al were systematically investigated by atomistic simulations,with a variety of dipole heights,orientations and annealing tempe *** results indicate that non-screw super-dipoles transform into locally stable dipolar or reconstructed cores at low temperature,while into isolated or interconnected point defect clusters and stacking fault tetrahedra at high temperature via short-range diffu ***-screw super-dipoles inγ-tial andα_(2)-Ti_(3)Al exhibit similar features as fcc and hcp metals,***,over long-term annealing where diffusion is significant,60°superdipoles inγ-tial are stable,whereas the stability of super-dipoles inα2-Ti3 Al increases with dipole height and orientation *** influence on mechanical properties can be well evaluated by integrating these results into mesoscale or constitutive models.

关键词： tial Dislocation Dipole Mechanical property Atomistic simulation

Processing tial-Based Alloy by Elemental Powder Metallurgy

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Journal of Materials Science & Technology 2000年第6期16卷 605-610页

作者： Yong LIU, Baiyun HUANG, Yuehui HE and Kechao ZHOU (National Key Laboratory for Powder Metallurgy, Central South University of Technology, Changsha 410083, China) [Manuscript received July 31, 1999, in revised form November 19, 1999] Natl. Key Lab. for Powder Metallurgy Central South Univ. of Technol. Changsha 410083 China

TiAI-based alloys with various compositions (including Ti-48Al, Ti-47Al-2Cr-2Nb, Ti-47Al-2Cr-2Nb-0.2B and Ti-47Al-3Cr, in mole fraction) had been prepared by elemental powder metallurgy (EPM). The results have shown that the density of the prepared Ti-48AI alloy increases with increasing hot pressing temperature up to 1300℃. The Ti-48AI alloy microstructure mainly consisted of island-like Ti3Al phase and tial matrix at hot pressing temperature below 1300℃, however, coarse α2/γ lamellar colonies and γ grains appeared at 1400℃. It has also indicated that the additions of elemental Cr and B can refine the alloy microstructure. The main microstructural inhomogeneity in EPM TiAI-based alloys was the island-like α2 phase or the aggregate of α2/γ lamellar colony, and such island-like structure will be inherited during subsequent heat treatment in (α＋γ) field. Only after heat treatment in a field would this structure be eliminated. The mechanical properties of EPM tial-based alloys with various compositions were tested, and the effect of alloy elements on the mechanical properties was closely related to that of alloy elements on the alloy microstructures. Based on the above results, TiAI-based alloy exhaust valves were fabricated by elemental powder metallurgy and diffusion joining. The automobile engine test had demonstrated that the performance of the manufactured valves was very promising for engine service.

关键词： tial Processing tial-Based Alloy by Elemental Powder Metallurgy

Electronic structure and physical property of tial

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中国有色金属学会会刊：英文版 1999年第4期9卷 672-676页

作者：高英俊陈振华黄培云钟夏平广西大学物理系广西南宁中南工业大学非平衡材料科学与工程所湖南长沙

Using a new developed valence bond theory of intermetallic compound, the electronic structure and properties of tial were analysed systematically. It was determined that the valence electronic structure of Ti and Al atom in tial to be [ (4sf)0.42 (4sc) 1.36 (3dc)2.22]Ti and[ (3sf)0.39 (3sc)0.59 (3dc)2.02 ] Al respectively. According to these electronic structure, lattice constant, cohesive energy, potential curve, bulk modulus and temperature dependence of linear thermal expansion coefficient have been calculated, most of the theoretical values of these properties are in good agreement with experiment ones.

关键词： tial electronic structure physical properties