The macro-scale and meso-scale simulation models of stainless steel clad plate were established by DEFORM-3D. The multi-scale coupling simulations of clad plate with different rolling parameters were carried out. The ...
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Stabilizing crane plays an important role in the lifting of cargo between ships and offshore platforms, such as wind turbine and drilling platform under high sea conditions. According to the characteristics of motion ...
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In the process of reciprocating bending, any particle of the workpiece is subjected to cyclic tensile compression deformation. The workpiece undergoes a reciprocating bending deformation process, and each particle und...
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In the process of reciprocating bending, any particle of the workpiece is subjected to cyclic tensile compression deformation. The workpiece undergoes a reciprocating bending deformation process, and each particle undergoes a cyclic tension-compression loading cycle. In this paper, cyclic tensile loading tests under different prestrains and strain amplitudes are carried out. The macroscopic behavior of 304 stainless steel and ST12 cold rolled plate under cyclic tension-compression loading and the effect of prestrain on the stable hysteresis loop of the two materials are studied. Thus, the evolution of macroscopic mechanical properties in the process of reciprocating bending deformation is deeply understood. The experimental results show that 304 stainless steel and ST12 cold rolled plate are characterized by cyclic softening; the prestrain has little effect on the stable hysteresis loop, the cyclic tension-compression loading eliminates the initial difference of the mechanical properties caused by the prestrain and makes the mechanical properties of materials tend to be uniform. It is also proved indirectly that the reciprocating bending has not only the effect of uniform curvature, but also makes the mechanical properties of the same layer of fibers be homogenized.
A novel 22MnMoB hot stamping steel was designed. The continuous cooling transformation （CCT） measurement of the 22MnMoB steel showed that the ferrite-bainite microstructure could be obtained at cooling rates lower t...
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A novel 22MnMoB hot stamping steel was designed. The continuous cooling transformation （CCT） measurement of the 22MnMoB steel showed that the ferrite-bainite microstructure could be obtained at cooling rates lower than 25 ℃/s, and the complete martensite structure required the cooling rate higher than 30 ℃/s. The experiments with non-uniform die temperatures were carried out to obtain tailored properties. The results showed that strength of 1 411 MPa and elon- gation of 6% could be obtained in the hard zone, and strength of 916 MPa and elongation of 9% could be obtained in the soft zone, which can be realized by controlling the die temperature at 400 ℃. The transition zone was found smooth and could be beneficial to reduce the stress concen tration and therefore improve the performance of components.
The effect of kinematic hardening behavior on the shakedown behaviors of structure has been investigated by performing shakedown analysis for some specific problems. The results obtained only show that the shakedown l...
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The effect of kinematic hardening behavior on the shakedown behaviors of structure has been investigated by performing shakedown analysis for some specific problems. The results obtained only show that the shakedown limit loads of structures with kinematic hardening model are larger than or equal to those with perfectly plastic model of the same initial yield stress. To further investigate the rules governing the different shakedown behaviors of kinematic hardening structures, the extended shakedown theorem for limited kinematic hardening is applied, the shakedown condition is then proposed, and a general analytical solution for the structural shakedown limit load is thus derived. The analytical shakedown limit loads for fully reversed cyclic loading and non-fully reversed cyclic loading are then given based on the general solution. The resulting analytical solution is applied to some specific problems： a hollow specimen subjected to tension and torsion, a flanged pipe subjected to pressure and axial force and a square plate with small central hole subjected to biaxial tension. The results obtained are compared with those in literatures, they are consistent with each other. Based on the resulting general analytical solution, rules governing the general effects of kinematic hardening behavior on the shakedown behavior of structure are clearly.
A co-simulation technology of casting-forging combination forming process was developed. Initial nonuniform cas-ting grain size was obtained from CAFE module of ProCAST software by casting simulation. A Fortran progra...
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Nonmetallic inclusions mixed into large forged metal objects destroy the continuity in the metal and affect the quality of the forged *** on how inclusions affect the plastic deformation of a matrix shows the signific...
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Nonmetallic inclusions mixed into large forged metal objects destroy the continuity in the metal and affect the quality of the forged *** on how inclusions affect the plastic deformation of a matrix shows the significance of the formation mechanism of inclusion *** upset forging,the nonlinear finite element model was shown to be appropriate for the ingot hot-forging process by comparing the results with experiments involving plastic and hard inclusions inserted into the forged *** high-temperature stress-strain curves of MnS plastic inclusions were obtained *** results show how,during upsetting,the morphology of MnS plastic inclusions varies from spherical to ellipsoidal,until finally becoming flat in *** larger the inclusion is,the larger the degree of deformation of the inclusion is,and large inclusions enhance the risk of the final product failing to pass inspection for inclusion *** significantly concentrates in the matrix near a hard *** the hard inclusion reaches a certain size,conical fractures form on both sides of the *** pass inclusion-flaw inspection and close hole defects to the extent possible,the flat-anvil upsetting is ***,the inclusiondeformation state obtained by finite element simulation is verified experimentally.
This paper constructs a man-machine integrated no-load static model considering the self-balancing of the mechanism, obtains the mapping relationship among joint variable, no-load torque, measured torque and end-force...
This paper constructs a man-machine integrated no-load static model considering the self-balancing of the mechanism, obtains the mapping relationship among joint variable, no-load torque, measured torque and end-force of the patient. According to the damping control strategy, the end force and speed mapping function planning is completed. The joint angular velocities based on the kinematic inverse solution are calculated, which are important parameter of man-machine coupling motion.
A new approach of CAD variation geometry is proposed for automatically establishing the simulation mechanisms of parallel manipulators (PMs) with linear legs, and automatically solving their forward displacements, wor...
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