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Development and Application of Ti-based Alloy Casting Technologies in the Field of Aerospace

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上海航天（中英文） 2022年第1期39卷 1-14页

作者： HOU Zhengquan LI Baohui FENG Gangwen WU Jingxi FAN Lipeng GUO Yingfei chen Yuyong chen Bin ZHANG Xuliang Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina

Ti-based alloys have been widely applied in the aerospace field,owing to their outstanding performance.Precision casting can be used to make integrated near-net-shape components with complex thin-walled structures,which will further promote the engineering application of Ti-based alloys. In this paper,the research progress of Tibased alloys,e. g.,high-temperature Ti-based alloys,high-strength Ti-based alloys,TiAl-based alloys,Ti-based matrix composites,and their precision casting technologies are reviewed. In addition,the development directions of Tibased alloys are presented based on the application status of Ti-based alloys in the aerospace field.

关键词： high-performance Ti-based alloy TiAl-based alloy Ti-based matrix composite precision casting aerospace

Effect of V and Nb additions on microstructure,properties,and deformability of Ti-45Al-9 (V,Nb,Y) alloy

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China Foundry 2010年第4期7卷 357-361页

作者： Yang Fei Kong Fantao chen Yuyong Xiao Shulong School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China Department of Powder Metallurgy. Guangzhou Research Institute of Non-ferrous Metals Guangzhou 510650 China

Ti-45Al-9(V, Nb, Y) alloys with four different x=V/Nb (atomic ratio x = 1, 1.5, 2 and 3.5) have been prepared, and the microstructures, properties and hot deformation behaviors were investigated. SEM, XRD and TEM results showed that Ti-45Al-9(V, Nb, Y) alloys were mainly composed of γ, α 2 , and β phase, and the volume fraction of β phase increased with the increase of the atomic ratio of V/Nb. The alloys were featured with lamellar microstructure with β and γ phases locating at the colony boundaries, and some β precipitates appearing at γ/γ interfaces. It was found that the colony size decreased with the increase of x. The alloys exhibited moderate mechanical properties at room temperature, with a yield strength of over 600 MPa, and fractures showed mainly translamellar character. The alloy with x=3.5 exhibited the best deformability at elevated temperature and that with x=1 had superior oxidation resistance at 800 ℃.

关键词： TiAl 合金微观结构和性质热变丑行为氧化

Genetic diversity and differentiation of masu salmon(Oncorhynchus masou masou)between and within cultured populations inferred from microsatellite DNA analysis

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Zoological Research 2012年第4期33卷 33-39页

作者： Zhiying JIA yuyong ZHANG Shuqiang chen Lianyu SHI Heilongjiang River Fisheries Research Institute Chinese Academy of Fishery SciencesHarbin 150070China College of Fisheries and Life Science Shanghai Ocean UniversityShanghai 201306China

Masu salmon,Oncorhynchus masou masou,is one of the most valuable fishery species that has been introduced to China,though to date no studies on the genetic diversity and genetic relationship among hatchery populations has been performed with molecular markers.We undertook such a study and sampled 120 individuals from three hatchery stocks and analyzed 20 microsatellite loci.All loci were polymorphic and a total of 91 alleles were detected.A relatively low level of genetic diversity was revealed with effective number of allele of 3.1094,3.3299 and 3.1894 and expected heterozygosity of 0.6600,0.6648 and 0.6638 in the three stocks,respectively.Deviations from Hardy-Weinberg equilibrium were found due to heterozygote deficit.Accordingly,evidence of genetic bottlenecks were found in the three stocks.An individual assignment test demonstrated that 85%of individuals were correctly assigned into their original stocks.Pairwise Fst revealed that significant differentiation occurred between these three stocks.The results of the study indicated that disequilibrium of genetic structure and differentiation has occurred in all three stocks.This information collectively provides a basis for measures to avoid of loss of genetic diversity and introgression in Chinese aquaculture.

关键词： Oncorhynchus masou masou Microsatellite Genetic diversity Genetic differentiation

Effect of yttrium on microstructure and mold filling capacity of a near-α high temperature titanium alloy

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China Foundry 2012年第4期9卷 344-348页

作者： Zhao Ertuan chen Yuyong Kong Fantao Zhang Changjiang Xiao Shulong National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

The addition of rare earth yttrium(Y) can improve the performances of high temperature titanium alloys,such as the tensile ductility,thermal stability and creep property,etc.However,few studies on the effect of Y on the castability of titanium alloys have been carried out,which is significant to fabrication of thin-walled complex titanium castings by investment casting.In this study,the microstructure and mold filling capacity of a Ti-1100 alloy with different Y additions(0,0.1wt.%,0.3wt.%,0.5wt.% and 1.0wt.%) were investigated systematically through investment casting experiments,and the casting experiments were carried out in a centrifugal titanium casting machine.The microstructures of the alloy were observed via the optical microscopy,scanning electron microscopy and transmission electron microscopy.The mold filling capacity was tested by using of a grid pattern and was evaluated by the number of segments completely filled by the cast alloy.The results indicate that the grain size is decreased and the mold filling capacity is improved significantly with increasing the addition of Y from 0 to 1.0wt.%.The average primary grain size of Ti-1100 alloy is reduced from 250 μm to 50 μm and the mold filling capacity is increased from 61.5% to 100%.Considering the potential harmful effect on tensile properties of titanium alloys due to high concentrations of Y,it is suggested that Y addition should be about 0.3wt.%.

关键词：金属材料钛材料钛合金组织结构

Pyrosequencing investigation into the influence of Cu^(2+),Zn^(2+),Fe^(2+)and I^- mixtures on fungal diversity and toxigenic fungal growth in a fermented liquid feed

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Animal Nutrition 2016年第1期2卷 51-56页

作者： yuyong He Zhiyu chen Hong Wen Wei Lu Huadong Wu Jiangxi Province Key Laboratory of Animal Nutrition Jiangxi Agricultural University Jiangxi Provincial Institute of Veterinary Drugs and Feed Control College of Animal Science and Technology Jiangxi Agricultural University

A L_9(3~4) orthogonal experiment was conducted to evaluate the influence of 9 mixtures which consisted of Cu^(2+), Zn^(2+), Fe^(2+) and I^- ions at different ion concentrations on fungal diversity and toxigenic fungal growth in a Bacillus subtilis-fermented liquid feed(FLF) using pyrosequencing. The maximal Chao estimator and Shannon index were achieved in the FLF with a mixture of Cu^(2+)(200 mg/kg), Zn^(2+)(160 mg/kg),Fe^(2+)(150 mg/kg) and I^-(2.4 mg/kg). The minimal relative abundance of Aspergillus was achieved when a mixture of Cu^(2+)(200 mg/kg),Zn^(2+), Fe^(2+) and I^-was added to the FLF. Compared with Zn^(2+), Fe^(2+) and I^-,Cu^(2+) was the most important ion in inhibitingAspergillus growth. Adding Zn^(2+)(160 mg/kg), Cu^(2+), Fe^(2+) and I^- to the FLF minimized the relative abundance ofFusarium. It was Zn^(2+) instead of Cu^(2+) played a critical role in suppressing the growth of Fusarium. The proper use of the mixture of Cu^(2+), Zn^(2+), Fe^(2+) and I^-in FLF contributes to inhibit the growth of mycotoxin-producing fungi during storage. The new findings of this study help farmers properly use the mixture of Cu^(2+),Zn^(2+), Fe^(2+) and I^- to inhibit the growth of mycotoxinproducing fungi in the production of high quality FLF and alleviate mycotoxins damages to animals and humans.

关键词： Trace elements Fungal growth Mixture of ions Fermented liquid feed Pyrosequencing

Preparation of big size open-cell aluminum foam board using infiltration casting

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China Foundry 2008年第4期5卷 240-243页

作者： wang Lucai chen Yuyong Wang Fang Wu Jianguo You Xiaohong School of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

This paper presents an infiltration casting technique for manufacturing big size open-cell aluminum foam boards.The principle and key technologies of infiltration casting are also analyzed.Based on the previous practice of the small size aluminum foam production,the die for preparing big size aluminum foam boards is designed and manufactured.The experiments on aluminum boards of 300 mm×300 mm×(20-75)mm,with the pore size ranging from 1.0 to 3.2 mm and average porosity of 60%,have been performed.The experimental results show that a reliable infiltration process depends critically on the pouring temperature of the molten Al-alloy,the preheated temperature of the mould and salt particles and vacuum.Current research explores the possibility of large-scale manufacturing and application of the aluminum foams.

关键词：铝合金铸件铸造工艺

Fabricating of Open-cell Porous Al-Si Alloy with Pressure Penetration Casting

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Journal of Materials Science & Technology 1999年第1期15卷 63-66页

作者： Xu, Qingyan chen, yuyong Li, Qingchun Harbin Inst Technol Met Casting Lab Harbin 150001 Peoples R China

Open-cell porous Al alloy was fabricated by pressure penetration method and the fabrication of preform was studied in detail. When forming temperature is about 700 degree C and binder content is about 10%, preform with high compressive strength was obtained. Good porous Al alloy with pore size 0.5-1.6 mm and porosity 60%-80% can be obtained under 100 degree C super-heating of liquid metal and about 1.0 MPa applied pressure. The size of the largest sample is up to 100 mm in diameter and 100 mm in height. With the help of SEM it was found that the obtained material is a three-dimensional open-cell porous structure with well-distributed and connected with each other pores. Finally, theoretical analysis was carried out to explain the effect of fabricating process. (Edited author abstract) 4 Refs.

关键词： Aluminum alloys

Influence of Voids on the Tensile Performance of Carbon/epoxy Fabric Laminates

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Journal of Materials Science & Technology 2011年第1期27卷 69-73页

作者： Hongyan Zhu Baochang Wu Dihong Li Dongxing Zhang yuyong chen School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Harbin Aircraft Industry Co. Ltd.Harbin 150060China

This paper aims at investigating the effect of voids on the tensile properties of [（±45）4/（0,90）/（±45）2] S and [（±45）/0 4/（±45）（0,90）] S composites.Specimens with void contents in the range of 0.4% to 9.0% were fabricated from carbon/epoxy fabric.The void content was determined by ultrasonic attenuation and optical image analysis,and microscopic inspection was also used to analyze the shape and size of the voids.The influence of voids on the tensile strength and modulus of both stacking sequence is compared in terms of the size and the shape of the voids.The effect of voids on the initiation and propagation of tensile failure of both stacking sequence composite was investigated.

关键词： Composite Void Tensile strength

Low-temperature superplasticity of β-stabilized Ti-43Al-9V-Y alloy sheet with bimodalγ-grain-size distribution

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Journal of Materials Science & Technology 2021年第36期95卷 225-236页

作者： Yu Zhang Shuai Chang yuyong chen Yuchao Bai Cuiling Zhao Xiaopeng Wang Jun Min Xue Hao Wang Department of Mechanical Engineering Faculty of EngineeringNational University of Singapore9 Engineering Drive 1Singapore 117575Singapore Department of Materials Science and Engineering Faculty of EngineeringNational University of Singapore9 Engineering Drive 1Singapore 117576Singapore State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

The superplasticity of Ti-43Al-9V-0.2Y alloy sheet hot-rolled at 1100℃was systematically investigated in the temperature range of 750-900℃under an initial strain rate of 10^(-4)s^(-1).A bimodalγgraindistribution microstructure of Ti Al alloy sheet,with abundant nano-scale or sub-micronγlaths embedded insideβmatrix,exhibits an impressive superplastic behaviour.This inhomogeneous microstructure shows low-temperature superplasticity with a strain-rate sensitivity exponent of m=0.27 at 800℃,which is the lowest temperature of superplastic deformation for Ti Al alloys attained so far.The maximum elongation reaches~360%at 900℃with an initial strain rate of 2.0×10^(-4)s^(-1).To elucidate the softening mechanism of the disorderedβphase during superplastic deformation,the changes of phase composition were investigated up to 1000℃using in situ high-temperature X-ray diffraction(XRD)in this study.The results indicate thatβphase does not undergo the transformation from an ordered L2;structure to a disordered A2 structure and cannot coordinate superplastic deformation as a lubricant.Based on the microstructural evolution and occurrence of bothγandβdynamic recrystallization(DR)after tensile tests as characterized with electron backscatter diffraction(EBSD),the superplastic deformation mechanism can be explained by the combination of DR and grain boundary slipping(GBS).In the early stage of superplastic deformation,DR is an important coordination mechanism as associated with the reduced cavitation and dislocation density with increasing tensile temperature.Sufficient DR can relieve stress concentration arising from dislocation piling-up at grain boundaries through the fragmentation from the original coarse structures into the fine equiaxed ones due to recrystallization,which further effectively suppresses apparent grain growth during superplastic deformation.At the late stage of superplastic deformation,these equiaxed grains make GBS prevalent,which can effectively avoid intergranular cracking and is conducive to the further imp

关键词： Titanium aluminides Hot-rolled alloy sheet Bimodal microstructure In situ high-temperature XRD Superplasticity