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Genetic background analysis and breed evaluation of Yiling yellow cattle

Journal of Integrative Agriculture 2017年第10期16卷 2246-2256页

作者： XU Ling ZHANG Wen-gang LI Jun-ya ZHU De-jiang XU Xiao-cheng TIAN Yan-zi XIONG Xiong GUO Ai-zhen CAO Bing-hai NIU Hong ZHU Bo WANG Ze-zhao LIANG Yong-hu SHEN Hong-xue chen Yan Cattle Genetics and Breeding Innovation Team Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing 100193 P.R.China Animal Husbandry Technical Extension Station of Yiling Yichang 443000 P.R.China Animal Husbandry and Veterinary Bureau of Yiling Yichang 443000 P.R.China The state key laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan 430070 P.R. China Department of Animal Genetics and Breeding College of Animal Science and Technology China Agricultural University Beijing 100193 P.R.China

Traditionally, Chinese indigenous cattle is geographically widespread. The present study analyzed based on genome-wide variants to evaluate the genetic background among 157 individuals from four representative indigenous cattle breeds of Hubei Province of China： Yiling yellow cattle （YL）, Bashan cattle （BS）, Wuling cattle （WL）, Zaobei cattle （ZB）, and 21 indi- viduals of Qinchuan cattle （QC） from the nearby Shanxi Province of China. Linkage disequilibrium （LD） analysis showed the LD of YL was the lowest （~=0.32） when the distance between markers was approximately 2 kb. Principle component analysis （PCA）, and neighbor-joining （NJ）-tree revealed a separation of Yiling yellow cattle from other geographic nearby local cattle breeds. In PCA plot, the YL and QC groups were segregated as expected; moreover, YL individuals clustered together more obviously. In the N J-tree, the YL group formed an independent branch and BS, WL, ZB groups were mixed. We then used the FST statistic approach to reveal long-term selection sweep of YL and other 4 cattle breeds. According to the selective sweep, we identified the unique pathways of YL, associated with production traits. Based on the results, it can be proposed that YL has its unique genetic characteristics of excellence resource, and it is an indispensable cattle breed in China.

关键词： Yiling yellow cattle breed evaluation principle component analysis neighbor-joining tree

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Simulation on the Melt Flow in Laser Full Penetration welding with a Model Including a Non-Rotational Symme-try keyhole Based on Energy Balance

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稀有金属材料与工程 2011年第S4期40卷 120-124页

作者： Zhang L J1,Zhang J X1,Wu B1,2,chen L2,Gong S L2,Wang H R3 1 state key laboratory of Mechanical Behavior for Materials,Xi’an Jiaotong University,Xi’an 710049,China2 Power Beam Processing Dept.,Avic Beijing Aeronautical Manufacturing Technology Research Institute,Beijing 100024,China3 School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China Xi An Jiao Tong Univ Sch Energy & Power Engn Xian 710049 Peoples R China Xi An Jiao Tong Univ State Key Lab Mech Behav Mat Xian 710049 Peoples R China Avic Beijing Aeronaut Mfg Technol Res Inst Power Beam Proc Dept Beijing 100024 Peoples R China

A three dimensional model including a non-rotational symmetry keyhole of which the geometry is calculated base on the energy balance at keyhole wall is created to simulate the heat transfer and fluid flow within the molten pool during laser full penetration welding of titanium alloy *** order to take into account the effects of multiple reflections within the keyhole,a ray tracing method is employed and the coordinate dependent heat flux obtained is exerted on keyhole wall during the simulation on the heat transfer and fluid flow within molten ***,the computed weld cross sectional profile is compared with the experimental result to verify the model and it is fond that the simulation result is consists with experimental result.

关键词： laser welding titanium alloy non-rotational symmetry keyhole simulation

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基于中间过渡层的5A06/0Cr18Ni10Ti气化冲击焊接工艺研究

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金属学报 2019年第8期55卷 1041-1048页

作者：苏珊陈树君肖珺 Yu MAO Anupam VIVEK Glenn DAEHN 北京工业大学汽车结构部件先进制造技术教育部工程研究中心北京100124 Impulse Manufacturing laboratory the Ohio State University Columbus 43211 USA

利用气化冲击焊接技术,制备了力学性能良好基于中间层的5A06铝合金与0Cr18Ni10Ti不锈钢气化冲击焊接接头,中间层3003铝合金与飞板5A06铝合金和靶板0Cr18Ni10Ti界面焊接良好,接头结合区域呈圆环状。通过信号采集系统分析了铝箔气化时间... 详细信息

利用气化冲击焊接技术,制备了力学性能良好基于中间层的5A06铝合金与0Cr18Ni10Ti不锈钢气化冲击焊接接头,中间层3003铝合金与飞板5A06铝合金和靶板0Cr18Ni10Ti界面焊接良好,接头结合区域呈圆环状。通过信号采集系统分析了铝箔气化时间和电流随能量输入的变化,采用OM和SEM分析了接头界面的微观形貌和元素分布。研究了能量输入对铝箔气化的时刻和接头力学性能的影响。结果表明,随着能量输入的增加,铝箔气化所需时间减小,最终碰撞速率增大,从而使焊接区域直径增大;接头的抗拉力和抗剪力随能量输入的增大而增大。当能量输入为9 kJ时,接头的最大抗拉力为44.0 k N,抗剪力为2.1 kN;5A06/3003界面呈中间对称波状结合,3003/0Cr18Ni10Ti界面以金属间化合物连接,结合区域错位分布。

关键词：中间过渡层异种材料气化冲击焊接光子多普勒测速

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气化冲击焊飞板碰撞速度测量及影响因素分析

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稀有金属材料与工程 2018年第11期47卷 3439-3443页

作者：陈树君苏珊肖珺毛羽 Anupam Vivik Glenn S.Daehn 北京工业大学汽车结构部件先进制造技术教育部工程研究中心北京100124 The Ohio state University Impulse Manufacturing LaboratoryColumbusOhio 43210USA

气化冲击焊接技术可广泛用于难以焊接成形的钛、镁和铝等有色金属材料与钢材的连接。铝箔作为气化冲击焊接过程能量转换的载体,它的工作效率对气化冲击焊接工艺起到至关重要的作用。分析了气化冲击焊接过程中能量转换的过程,采用光子多... 详细信息

气化冲击焊接技术可广泛用于难以焊接成形的钛、镁和铝等有色金属材料与钢材的连接。铝箔作为气化冲击焊接过程能量转换的载体,它的工作效率对气化冲击焊接工艺起到至关重要的作用。分析了气化冲击焊接过程中能量转换的过程,采用光子多普勒测速系统分析了3种不同厚度的铝箔在不同能量输入条件下铝箔的工作效率和对飞板与靶板碰撞速度的影响规律。结果表明,当飞板与靶板间距(碰撞角度5o)为2.5 mm时,铝箔的气化能量是影响飞板与靶板碰撞速度的关键因素。通过碰撞速度的分析可以发现,0.051 mm铝箔在输入能量小于3 kJ时效率最高,0.076 mm铝箔在3～6 kJ效率最高,6～12 kJ时,0.127 mm的铝箔可以获得最佳效率。

关键词：铝箔气化冲击焊光子多普勒测速能量转换:碰撞速度

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Analysis of Electrical Characteristics of Inter-wire Arc in Cross-Coupling Arc

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 203-211页

作者： Zhenyang Lu Shanwen Dong Fan Jiang cheng Li College of Mechanical Engineering and Applied Electronics Technology Ministry of Education Engineering Research Center of Advanced Manufacturing Technology for Automotive Components Beijing University of Technology

As a new composite welding heat source introduced in recent years, the cross-coupling arc uses a non-consumable electrode arc(plasma arc) and a consumable electrode arc(inter-wire arc) in cross-coupling, in which the plasma arc is the main arc and the inter-wire arc is the vice arc, to realize the separate control of the heat input to the workpiece,arc force, and droplet transfer. To reveal the electrical characteristics of the inter-wire arc under the action of the plasma arc, in this study, rotating probes are used to sweep across the plasma arc. When the probes rotate into the plasma arc, a circuit is formed, and the electrical characteristics of the inter-wire arc are indirectly analyzed according to the circuit: the probe centering current and input voltage are used as the physical quantities. The results show that at a certain wire feed rate, the inter-wire arc current increases with increasing input voltage. When the input voltage is low, the wire feed rate has no obvious e ect on the inter-wire arc current. At a higher input voltage, where the wire feed rate is high, the inter-wire arc current decreases. With the increase in the plasma arc current, the inter-wire arc current first increases quickly and then increases slowly, and simultaneously, the striking arc time becomes *** the increase in the interval between the nozzle and the workpiece, the inter-wire arc current increases, but when the arc length increases to a certain limit, the slope of the welding current clearly declines.

关键词： Inter-wire arc Circuit Input voltage Inter-wire arc current

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Understanding the mechanisms of friction stir welding based on computer simulation using particles

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Defence Technology（防务技术） 2018年第6期14卷 643-656页

作者： A.Yu.Smolin E.V.Shilko S.V.Astafurov E.A.Kolubaev G.M.Eremina S.G.Psakhie Institute of Strength Physics and Materials Science SB RAS Tomsk634055Russia Tomsk state University Tomsk634050Russia Skolkovo Institute of Science and Technology Skolkovo143025Russia

Friction stir welding(FSW) is a novel technique for joining different materials without melting. In FSW the welded components are joined by stirring the plasticized material of the welded edges with a special rotating pin plunged into the material and moving along the joint line. From the scientific point of view,the key role of the FSW processes belongs to formation of the special plasticized conditions and activation of physical mechanisms of mixing the materials in such conditions to produce the strong homogeneous weld. But it is still a lack of complete understanding of what are these conditions and *** paper is devoted to understanding the mechanisms of material mixing in conditions of FSW based on a computer simulation using particles. The movable cellular automaton method(MCA), which is a representative of the particle methods in mechanics of materials, was used to perform all ***, material flow including material stirring in FSW is simulated using computational fluid mechanics or smoothed particle hydrodynamics, which assume that the material is a continuum and does not take into account the material structure. MCA considers a material as an ensemble of bonded particles. Breaking of inter-particle bonds and formation of new bonds enables simulation of crack nucleation and healing, as well as mass mixing and *** paper consists of two main parts. In the first part, the simulations in 2 D statements are performed to study the dynamics of friction stir welding of duralumin plates and influence of different welding regimes on the features of the material stirring and temperature distribution in the forming welded joints. It is shown that the ratio of the rotational speed to the advancing velocity of the tool has a dramatic effect on the joint quality. A suitable choice of these parameters combined with additional ultrasonic impact could considerably reduce the number of pores and microcracks in the weld without significa

关键词： Friction stir welding Plastic flow Deformation mechanisms Simulation Particle method

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Relating Initial Texture to Deformation Behavior During Cold Rolling and Static Recrystallization Upon Subsequent Annealing of an Extruded WE43 Alloy

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Acta Metallurgica Sinica(English Letters) 2022年第11期35卷 1793-1811页

作者： Qinghang Wang Haowei Zhai Hongbo Xia Lintao Liu Junjie He Dabiao Xia Hong Yang Bin Jiang School of Mechanical Engineering Yangzhou UniversityYangzhou 225127China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of Materials and Energy Yunnan UniversityKunming 650599China The Center of New Energy Materials and Manufacturing Jihua LaboratoryFoshan 528000China

Deformation behaviors during cold rolling and static recrystallization behaviors upon subsequent annealing of an extruded WE43 alloys with different initial textures were investigated in this *** types of differently textured WE43 initial alloys were labeled as samplesⅠ,ⅡandⅢ.The results showed that multiple twinning modes and basal slip dominated the deformation of samples during cold ***-rolled sampleⅠactivated the larger number of double twins with high strain energy,accompanied by the more uniform strain distribution,than cold-rolled samplesⅡandⅢ.During subsequent annealing,recrystallized grains preferentially occurred in double twins,twin-twin intersections and grain boundaries,thereby making cold-rolled sampleⅠhave the more rapid recrystallization *** recrystallization textures formed in three types of cold-rolled samples at the recrystallization nucleation stage,and they never largely changed with the annealing time due to the uniform grain growth induced by the solute drag and the precipitation pinning at grain *** full recrystallization,the grain growth was controlled by the solute drag,instead of precipitates which were re-dissolved into the ***,the nucleation and growth kinetics of static recrystallization were calculated,and the effects of initial texture on activation energies of recrystallization nucleation and growth were discussed.

关键词： WE43 alloy Texture Cold rolling Annealing Static recrystallization

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铝合金与镀锌钢板回填式搅拌摩擦点焊机制

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精密成形工程 2019年第6期11卷 42-46页

作者：申志康刘小超陈海燕李文亚 DING Yuquan chen James GERLICH Adrian 西北工业大学材料学院凝固技术国家重点实验室陕西省摩擦焊接技术重点实验室西安710072 University of Waterloo Centre for advanced Materials joining Ontario Waterloo N2l 3G1 Natural Resources Canada Canmet MATERIALS Ontario Hamilton L8P 0A5

目的研究铝合金与镀锌钢板回填式搅拌摩擦点焊界面组织演变机制与焊接工艺参数对力学性能的影响规律。方法采用连续焊接和改变焊接工艺参数的方法,分析了焊具自摩擦对焊接温度和接头力学性能的影响。采用电镜研究了铝合金与镀锌钢板连... 详细信息

目的研究铝合金与镀锌钢板回填式搅拌摩擦点焊界面组织演变机制与焊接工艺参数对力学性能的影响规律。方法采用连续焊接和改变焊接工艺参数的方法,分析了焊具自摩擦对焊接温度和接头力学性能的影响。采用电镜研究了铝合金与镀锌钢板连接界面的显微组织分布和焊接工艺参数对焊接温度及接头力学性能之间的内在关系。结果焊具的自摩擦及重复性预热影响焊具温度和接头力学性能,其作用远大于焊接工艺参数的影响。镀锌层阻止了被焊材料的直接接触而避免了大量金属间化合物的形成,镀锌层和铝合金反应生成固溶体组织,从而提高了铝合金与钢的焊接性。此外,液态的锌被挤出搅拌区,形成钎焊的连接机制,增大了接头连接面积和强度。最佳焊接工艺参数为:旋转频率1800 r/min,套筒下压量1.0 mm,停留时间3 s。在此焊接规范下,接头最大接头剪切强度为6.23 kN,且76.2%的焊点力学性能满足工业使用标准。结论回填式搅拌摩擦点焊是实现铝合金与镀锌钢板高质量连接的可靠方式。

关键词：回填式搅拌摩擦点焊铝合金镀锌钢板连接机制力学性能

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Cr3轧辊局部修复工艺的焊接热模拟分析

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焊接 2008年第3期 39-43页

作者：陈冰泉张正华黄永溪历雷钧吕奎清武汉理工大学材料加工工程系 430063 中钢邢台机械轧辊有限公司修复公司 054025 Department of Mechanical&Aerospace Engineering Utah State University 武汉铁锚焊接材料股份有限公司 430084

利用焊接工艺试验和热模拟试验研究了预热温度和冷速对高碳含量的轧辊材料Cr3钢焊接性的影响。通过金相分析、X射线衍射分析及温度-体积变化关系的分析,研究了预热温度和冷速影响Cr3钢焊接性的机理,确定了Cr3钢在焊接冷速下的组织,得到... 详细信息

利用焊接工艺试验和热模拟试验研究了预热温度和冷速对高碳含量的轧辊材料Cr3钢焊接性的影响。通过金相分析、X射线衍射分析及温度-体积变化关系的分析,研究了预热温度和冷速影响Cr3钢焊接性的机理,确定了Cr3钢在焊接冷速下的组织,得到了冷却速度与焊后组织、加热区最大收缩量和焊接残余应力的关系。研究表明,控制焊接时的冷却速度是保证这类轧辊材料堆焊修复质量的关键。

关键词：轧辊材料Cr3钢局部修复热模拟

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