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Robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 154-168页

作者： Fei Weng Guijun Bi Youxiang Chew Shang Sui Chaolin Tan zh.nglin Du Jinlong Su Fern Lan ng Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong Engineering&Technology Research Center for Superhard MaterialSchool of Materials Science and EngineeringShandong UniversityJinan 250061China Institute of Intelligent Manufacturing Guangdong Academy of SciencesGuangzhou 510095China Singapore Institute of Manufacturing Technology 5 Cleantech Loop636732Singapore

The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(LAAM_(p))and wire(LAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for LAAM_(p) and LAAM_(w),*** the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire *** characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α *** mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and *** mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material Specifications(AMS 6932)even without post heat *** fracture occurred within the interfacial area,further suggesting the robust *** findings of this study highlighted the feasibility of combining LAAM_(p) and LAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition.

关键词： laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior

REACTION OF 3,7-DINITRODIBENZOBROMOLIUM BISULFATE WIThSOME NUCLEOPhILES

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Chinese Chemical Letters 1996年第6期7卷 505-506页

作者： hou, ZJ zh.ng, h zh.ng, zh LANzhOU UNIV INST ORGAN CHEMLANZHOU 730000PEOPLES R CHINA LANzhOU UNIV STATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

Reaction of 3,7-dinitrodibenzobromolium bisulfate with some nucleophiles were studied. Primary products of reactions ore 2-bromo-2'-Nu-4-4'-dinitro-biphenyls.

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Master equation,design equations and runaway speed of the Kaplan turbine

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Journal of hydrodynamics 2021年第2期33卷 282-300页

作者： zh.zh.ng zhAW Zurch University of Applied ScienceZurichSwitzerland

To make the Kaplan turbine technology comparable to both the Pelton and the Francis turbine,the master equation for the Kaplan turbine has been established by analyses similar to that-for the Francis *** analysis begins with the descriptions of free vortex flows at the runner inlet and the swirl flow at the impeller *** considering the Euler equation for specific work and by further evaluating the most significant shock and swirling losses,the first and the second energy equations in the form of hydraulic efficiency were *** master equation is then established by combining both energy *** addition,three design equations and a new design parameter are *** master equation relates the turbine hydromechanics to the geometrical design of both the runner and the guide-vane *** enables the complete hydraulic characteristics of a given Kaplan turbine to be analytically and simply computed.A computation example demonstrates the functionality and applicability of the *** the reconstructed master equation,the runaway speed of the Kaplan turbine and its dependence on the guide-vane setting can be easily and precisely *** bulb turbines with guide vanes directly ahead of the turbine runner in the same tube,all computations are also applicable using another equivalent control parameter.

关键词： Kaplan turbine master equation design equations design parameter runaway speed hydraulic efficiency shock loss swirling loss bulb turbines

Selective De-O-acetylation in TCP-containing Carbohydrate Structures with Magnesium Methoxide

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维普期刊数据库

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Chinese Chemical Letters 2000年第11期11卷 941-944页

作者： Qin, zh Li, h Cai, MS Li, ZJ Beijing Med Univ Sch Pharmaceut Sci Dept Bioorgan Chem Beijing 100083 Peoples R China

Magnesium methoxide can be used for TCP-containing substrates to remove acetyl group successfully while leaving the TCP-group virtually intact.

关键词： OCh TCP De

Master equation and runaway speed of the Francis turbine

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Journal of hydrodynamics 2018年第2期30卷 203-217页

作者： zh.zh.ng Free Researcher Zurich Switzerland

The master equation of the Francis turbine is derived based on the combination of the angular momentum（Euler） and the energy laws. It relates the geometrical design of the impeller and the regulation settings（guide vane angle and rotational speed） to the discharge and the power output. The master equation, thus, enables the complete characteristics of a given Francis turbine to be easily computed. While applying the energy law, both the shock loss at the impeller inlet and the swirling loss at the impeller exit are taken into account. These are main losses which occur at both the partial load and the overloads and, thus, dominantly influence the characteristics of the Francis turbine. They also totally govern the discharge of the water through the impeller when the impeller is found in the standstill. The computations have been performed for the discharge, the hydraulic torque and the hydraulic efficiency. They were also compared with the available measurements on a model turbine. Excellent agreement has been achieved. The computations also enable the runaway speed of the Francis turbine and the related discharge to be determined as a function of the setting angle of the guide vanes.

关键词： Francis turbine master equation runaway speed hydraulic efficiency shock loss swirling loss streamline similarity method

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Journal of hydrodynamics 2018年第1期30卷 140-152页

作者： zh.zh.ng Free Researcher Zurich Switzerland

An analytical method is presented, which enables the non-uniform velocity and pressure distributions at the impeller inlet of a pump to be accurately computed. The analyses are based on the potential flow theory and the geometrical similarity of the streamline distribution along the leading edge of the impeller blades. The method is thus called streamline similarity method（SSM）. The obtained geometrical form of the flow distribution is then simply described by the geometrical variable G（s） and the first structural constant G_Ⅰ. As clearly demonstrated and also validated by experiments, both the flow velocity and the pressure distributions at the impeller inlet are usually highly non-uniform. This knowledge is indispensible for impeller blade designs to fulfill the shockless inlet flow condition. By introducing the second structural constant G_Ⅱ, the paper also presents the simple and accurate computation of the shock loss, which occurs at the impeller inlet. The introduction of two structural constants contributes immensely to the enhancement of the computational accuracies. As further indicated, all computations presented in this paper can also be well applied to the non-uniform exit flow out of an impeller of the Francis turbine for accurately computing the related mean values.

关键词： Pumps streamline similarity method flow distribution shock loss structural constant

Measuring gravitational effect of superintense laser by spin-squeezed Bose-Einstein condensates interferometer

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Chinese Physics B 2022年第5期31卷 265-273页

作者： Eng Boon ng C.h.Raymond Ooi Department of Physics University of MalayaKuala Lumpur 50603Malaysia

We consider an extremely intense laser,enclosed by an atom *** gravitational potential generated from the high-intensity laser is solved from the Einstein field equation under the Newtonian *** compute the strength of the gravitational force and study the feasibility of measuring the force by the atom *** intense laser field from the laser pulse can induce a phase change in the interferometer with Bose-Einstein *** push up the sensitivity limit of the interferometer with Bose-Einstein condensates by spin-squeezing effect and determine the sensitivity gap for measuring the gravitational effect from intense laser by atom interferometer.

关键词： intense laser field atom interferometer Bose-Einstein condensates spin-squeezing

The W-11-4A Platform Comprehensive Strength Monitoring System

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China Ocean Engineering 1998年第2期13卷 135-146页

作者： Shen, zh Li, h Xue, YI Chen, JC zhao, Q Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Louisiana Tech Univ Appl & Computat Anal & Modeling Program Ruston LA 71272 USA Acad Sinica S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

A comprehensive strength monitoring system used on a fixed jacket platform is presented in this paper. The long-term monitoring of W-11-4A platform achieved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, have been obtained. The emphasis of the paper is placed on the system design, and the instrumentation and operation methodology employed in the monitoring of the structural responses. The performance of the system and the characteristic results obtained during its 13-month operation are also summarized.

关键词： monitoring techniques comprehensive strength monitoring structural responses waterproof strain transducers underwater instrumentation techniques

SUBSTRUCTURE PRECONDITIONERS FOR NONCONFORMIng PLATE ELEMENTS

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Journal of Computational Mathematics 1998年第4期16卷 289-304页

作者： Shi, ZC Xie, zh Chinese Acad Sci ICMSEC State Key Lab Sci & Engn Comp Beijing 100080 Peoples R China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100080 Peoples R China

In this paper, we consider the problem of solving finite element equations of biharmonic Dirichlet problems. We divide the given domain into non-overlapping subdomains, construct a preconditioner for Morley element by substructuring on the basis of a function decomposition for discrete biharmonic functions. The function decomposition is introduced by partitioning these finite element functions into the low and high frequency components through the intergrid transfer operators between coarse mesh and fine mesh, and the conforming interpolation operators. The method leads to a preconditioned system with the condition number bounded by C(1 + log(2) h/h) in the case with interior cross points, and by C in the case without interior cross points, where h is the subdomain size and h is the mesh size. These techniques are applicable to other nonconforming elements and are well suited to a parallel computation.

关键词： substructure preconditioner biharmonic equation nonconforming plate element