力学进展

2006, 36(4): . doi: 10.6052/1000-0992-2006-4-J2006-113

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2006, 36(4): 0-iv. doi: 10.6052/1000-0992-2006-4-J2006-165

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2006, 36(4): 0-viii. doi: 10.6052/1000-0992-2006-4-J2006-166

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2006, 36(4): 481-484. doi: 10.6052/1000-0992-2006-4-J2006-155

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2006, 36(4): 485-506. doi: 10.6052/1000-0992-2006-4-J2004-139

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This paper reviews the research on deformationand fracture of the functionally ferromagnetic materials in the past severaldecades, especially in the recent decade or so. Problems of classicalmagnetoelasticity have been studied for a long time and a large numberof papersresults have been published. Along with the development ofsmart materials and structures in recent years, the functionallyferromagnetic materials, such as the giant magnetostrictive materials ofrare earth, ferromagnetic shape memory alloys and the ferromagneticcomposites, have attracted great attention. A lot of studies concern thedeformation and fracture of the functionally ferromagnetic materials and theeffective properties of ferromagnetic composites. In this paper, abrief introduction is firstly given to the research background of theclassical magnetoelasticity and the mechanical and magnetic behavior of thetraditional ferromagnetic structures. The research achievements on deformation and fracture behavior of the softferromagnetic materials and the mechanics of the ferromagnetic compositesare presented and commented extensively. Also discussed are the authors'studiesin recent years both on the experimental techniques of thefunctionally ferromagnetic materials, and the theoretical work on themesomechanics of the ferromagnetic composites, the magnetomechanicaldeformation and fracture mechanics of the soft ferromagnetic materials andsmart ferromagnetic shape memory materials. Finally, some topics forfurther studies are pointed out.

2006, 36(4): 507-516. doi: 10.6052/1000-0992-2006-4-J2005-082

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This paper introduces first the features of interfacial microstructures and failuremodes of polymer composites. The progress of experimental study on theinterfacial properties of particle-filled polymers and blended polymers, as well as the testing methods and results obtained for interfacial properties are reviewed.The testing methods from macro-tension to in-situ meso-tension arediscussed, as well as the analytical methods from fractured surface micrographs to strength andenergy calculation. The advantages and disadvantages of those methods are analyzedat different scales. Finally, it isindicated that the major difficulties for interfacial characterizationby tests are related to the apparatus performance and the advanced testing methods. In order to get reliableproperties of the interface, one should be able to design the interface easyto be characterized, and to invent new techniques of testing.

2006, 36(4): 517-535. doi: 10.6052/1000-0992-2006-4-J2005-136

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Ultra-light porous metals are novel multi-functinal materials, following the rapid development of new manufacturing technologies and materialsprocessing. In this paper, a state-of-the-art review of the research and developmentonporous cellular metals is presented, including stochastic metallic foams and periodiclattice metals. New research directions about these materials are also discussed,withemphasis placed on their multifunctionality and commercial applications.

2006, 36(4): 536-552. doi: 10.6052/1000-0992-2006-4-J2005-120

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The review considers the experiments of biologicalmechanics with coupling of force and electric field with biological moleculesand materials in probe techniques. Experimental methods and mainresearch findings are summarized systemically about the mechanicalproperties of biological molecules and materials at nano-scale at the tipsof scanning probe microscope, optical tweezers, magnetic tweezers and so on.Then the advances in molecular biological and physical mechanics studies inthe tiny and super-special environment between the tip and the substrateare discussed. Probe techniques have significant importance in revealing thephysical mechanical properties of biological molecules (including DNA andproteins), characterizing the structures of biological materials and formolecular bionics. It is envisaged that molecular biological and physicalmechanics studies in the multi-field coupling environments under the probetips will be an important field for future researches. It is necessary tocombine experimental investigations with theoretical analyses andcomputational simulations in the tip mechanics, and the development inthe virtual experimental technique of molecular physical mechanics will be animportant trend.

2006, 36(4): 553-563. doi: 10.6052/1000-0992-2006-4-J2005-123

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Active balancing technology can reduce vibration in time bythe adjusting the unbalanced state during the operation of a rotating machine, so as tokeep it in a stable state. Early balancing devices, dating from thelate of the 19$^{\rm th}$ century, include those of liquid type, ring type, ball type and pendulumtype; beginning from the middle of the 1960s one sees sprayingtype, electro-erosion type, electro-ray type, laser type and electrochemicaltype; and beginning from the late of the 20$^{\rm th}$ century,motor type and remote control type; and modern balancing devicesinclude those of hydraulic type, electromagnetic type and electromagnetic bearingtype. The mechanical structures and operating principles of each type ofon-line automatic balancing devices used in the rotating machine at home andabroad are summarized in this paper. The hydraulicand electromagnetic balancing devices are particularly addressed.The current research findings on the on-line active balancing technology arediscussed, and the engineering application examples are given. The experiments using theelectromagnetic active balancing device to solve the vibration problem of the flexible rotor with bending fault and the hypergravity machine rotor areintroduced. The on-line active balancing technology has been applied to themachining tools to improve the working accuracy, such as the grindingmachine . The active balancing devices have been used in thelarge-sized rotating machines with tremendous economic returns, suchas steam turbines, fans and compressor engines. Some key problemsincluding the balancing actuator with high reliability and the controlstrategy with high efficiency have not been completely solved.

2006, 36(4): 564-570. doi: 10.6052/1000-0992-2006-4-J2005-007

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Precision machining of thin-walled complex aeroenginecomponents is one of the most critical requirements to achieve theirexcellent performance. Achieving the right profile for complex partsincreasingly depends on the use of CAD/CAM packages for defining optimalcutting strategies and tool paths. However, most of the existing multi-axisCNC programming key techniques are based only on the idealized geometry anddo not take into account factors such as cutting force induced part/tooldeflection. As a result, there is usually a significant deviation betweenthe planned and machined part profiles. In order to avoid these undesirableresults, such as over-cut or under-cut, production-planning engineers areconservative in the selections of process parameters. In this paper,different approaches of cutting force modeling are discussed, which includechip formation or tool-chip interface friction based analytic force modelfor orthogonal cutting, milling force model based on the cuttingcoefficients, artificial neural networks, and fuzzy-grey theory. The keyis topredict the workpiece/tool deformation, optimize the key process parameters,compensate the tool paths, and realize the physical simulation of machiningprocess.

2006, 36(4): 571-579. doi: 10.6052/1000-0992-2006-4-J2005-083

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Supercavitation technology can reduce drags ofunderwater vehicles up to 90{\%} percent. With theadvanced propulsion technology, a super-high speed can be achieved, just likeflying in the air. Supercavitation technology has a remarkable impact on theresearch of naval weapons. Russia has successfully developed the Shkvaltorpedo, which can travel at about 100m/s under water. The researches ontheoretical basis and applications of supercavitation technology are carried out in manyother countries, such as the US, Germany, French and so on,and also in our country in recent years. The currentstatus, problems and applications of supercavitation technology are reviewedin this paper. The basic principle of cavitation, the conception ofsupercavitation and its drag reduction mechanism are introduced first. Somekey questions are summarized, including design of cavitator, generation andcontrol of ventilated supercavitation, stability of cavity and supercavitationvehicle. Then the research progress of the numerical simulation andexperimental approaches of supercavitation technology are reviewed. At theend, some difficulties with respect to large-scale supercavitation weaponsare analyzed, and further research topics in this field are suggested.

2006, 36(4): 580-590. doi: 10.6052/1000-0992-2006-4-J2005-114

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To analyze the relations between the sand transport rate andthe forcing wind, a high sampling frequency is necessary for themeasurement of the wind velocity and the sand transport rate. This paper reviews the development ofmeasurement techniques related to wind-sand flows in pastseveral decades. Merits and demerits of conventional measurement devices forthe wind velocity and the sand transport rate are discussed in detail. Moreover,the Particle Image Velocimetry (PIV), a new optical velocity measurementtechnique is specially addressed in this paper, which has great potentialapplications in the wind-sand flow experiment. Based on the PIV technique, not onlythe macro information such as two phase velocity field of wind and sand,wind sand flow integral structure, but also micro information such assingle grain motion, can be obtained.

2006, 36(4): 591-598. doi: 10.6052/1000-0992-2006-4-J2005-063

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Because of the decoupling of the velocity and the pressure computation, the projectionmethod is much more efficient than the fully coupled procedures. This notable advantage hasattracted great attention, and many improved projection methods havebeendeveloped duringthe past 20 years. The projection methods are currently among the most popular methods forsolving viscous incompressible flow based on the primitive variable formulations. According totheir processes of construction, the projection methods are classified into three types in thepresent paper, namely, the Helmholtz-Hodge decomposition projection methods, the operatorsplitting projection methods and the local continuous projection methods. Their development andsolution procedures are introduced in details. From the solution procedures, it is found that thevelocity-pressure decoupling makes it difficult to analyze the accuracy of the projection method,which has often been a subject for debating. Generally speaking, high order convergence in timefor the velocity can be readily obtained, while the computed pressure is typically only first orderaccurate in time. However, by comparing and analyzing the three types of the projection methods,we show that the local continuous projection methods make it possible to develop high orderaccurate projection methods both theoretically and practically, whichmay clarifysome misunderstandings about the accuracy of projection methods.

2006, 36(4): 599-610. doi: 10.6052/1000-0992-2006-4-J2005-103

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Particulate materials are often in the form of powderswhich are themselves agglomerations of much smaller primary particles.A common problem in the handling of powders is the degradationdue to attrition and/or fragmentation of agglomerates as theycollide with each other and with the process equipment. Impact breakage hasbeen studied experimentally for many years. However, information from thoseexperiments is normally restricted to post-impact examinations of thefragments and debris produced during the short duration of an impact event.Numerical simulations of agglomerate impact fracture, especially usingdiscrete element method, have achieved great successes over the pastdecade. New theories based on modern contact mechanics and new concepts havebeen proposed to study the mechanism of agglomerate impact breakage. Thispaper gives a brief review on the current development of the research,and also describes the simulation techniques of agglomerate impact.

2006, 36(4): 611-618. doi: 10.6052/1000-0992-2006-4-J2005-115

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A thermomechanical framework for modeling soils ispresented in this paper. The essence of the theory is to establishconstitutive relationships by using free energy and dissipation functionsthrough a fixed framework and procedure. The theory of internalvariables and the methodof Legendre transformation to determine the relationships among free energyfunctions as well as the relationship between dissipation and yield functionsare briefly discussed, the steps of formulating constitutive equationswithin this framework are also presented. The significance of soilconstitutive relationships and its relation with applications arediscussed.

2006, 36(4): 626-627. doi: 10.6052/1000-0992-2006-4-J2006-074

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2006, 36(4): 628-632. doi: 10.6052/1000-0992-2006-4-J2006-150

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