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基于Dynaform的三通管件液压成形影响因素分析 总被引:1,自引:0,他引:1
通过采用Dynaform软件对三通管件液压成形过程进行模拟仿真,确定了影响其成形质量的因素,得到了各参数对管件成形的影响规律,通过控制各参数可有效地提高三通管件液压成形的质量,提高生产效率。 相似文献
73.
Experimental study and finite element analysis of simple X- and T-branch tube hydroforming processes 总被引:2,自引:0,他引:2
The tube hydroforming process is a relatively complex manufacturing process; the performance of this process depends on various factors and requires proper combination of part design, material selection and boundary conditions. Due to the complex nature of the process, the best method to study the behaviour of the process is by using numerical techniques and advanced explicit finite element (FE) codes. In this work, X- and T-branch components were formed using a tube hydroforming machine and experimental load paths (forming pressure and axial feed) were obtained for the processes via a data acquisition system integrated with the machine. Subsequently, the processes were simulated using LS-DYNA3D explicit FE code using the same experimental boundary, loading conditions and the simulation results were compared with the experimental results. It was found that the developed branch height and the wall thickness distribution along different planes were in good agreement with the experimental results. 相似文献
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Mehdi Imaninejad Ghatu Subhash Adam Loukus 《International Journal of Mechanical Sciences》2004,46(8):1195-1212
Tube hydroforming experiments were conducted to develop the forming limit diagram of AA6082-T4 by utilizing three types of end-conditions: (i) “free-end”, (ii) “pinched-end” or “fixed-end” and (iii) “forced-end”. It was found that “free-end” hydroforming gives the lowest forming limits followed by “pinched-end” and “forced-end” hydroforming. It was noticed that the tube failure occurs within 5° to the extrusion weld in the “free-end” experiments, within 7° in the “pinched-end” condition and extended up to 10° in the “forced-end” hydroforming experiments. Finite element simulations were carried out to capture the effects of the weld geometry, weld mechanical properties and the end-conditions of the extruded tube on the maximum induced stress and location of the maximum von Mises stress. It was found that the anisotropy of the weld material and the end-condition used during hydroforming experiments have the largest influence on the failure location with respect to the weld center. 相似文献
76.
Three possible failure modes have been identified in tube hydroforming: buckling, wrinkling and bursting. A general theoretical framework is proposed for analyzing these failure modes as an elastoplastic bifurcation problem. This framework enables advanced yield criteria and various strain-hardening laws to be readily incorporated into the analysis. The effect of plastic deformation on the geometric instability in tube hydroforming, such as global buckling, axisymmetric wrinkling and asymmetric wrinkling, is precisely treated by using the exact plane stress moduli tensor. A mathematical formulation for predicting the localized condition for bursting failure is established herein. Furthermore, the critical conditions governing the onset of buckling, axisymmetric wrinkling and asymmetric wrinkling are derived in closed-form expressions for the critical axial compressive stresses. Closed-form solutions for the critical stress are developed based on Neale–Hutchinson's constitutive equation and an assumed deformation theory of plasticity. It is demonstrated that the onset of asymmetric wrinkling always requires a higher critical axial compressive stress than the axisymmetric one under the context of tube hydroforming with applied internal pressure and hence the asymmetric wrinkling mode can be excluded in the analysis of tube hydroforming. Parametric studies show that buckling and axisymmetric wrinkling are strongly dependent on geometric parameters such as t0/r0 and r0/ℓ0, and that axisymmetric wrinkling is the predominant mode for short tubes while global buckling occurs for long slender tubes. 相似文献
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针对自行设计的液压成形设备运行时需要记录实验数据,设计了基于数据采集卡(DAQ卡)的液压成形数据采集系统,利用Visual Basic编制界面和采集程序,由数据采集卡实现对成形压力和工件的轴向位移进行实时采集和A/D转换,由计算机完成数据的处理、保存和实时数据、波形的显示,为分析试件成形结果和设计合理的加载路径提供了必要的数据。 相似文献
79.
与传统冲压焊接工艺相比,管件内高压成形工艺具有成形精度高、质量轻、材料省等优点。因此,管件内高压成形技术成为从制造工艺上降低车身质量的主要途径之一。利用自制设备对简单管件进行内高压成形实验,并借助有限元软件对其成形全过程进行数值模拟,通过实验验证仿真结果的正确性和可靠性。基于此,对发动机横梁内高压成形过程进行仿真分析,主要研究摩擦因数、轴向补料路径对成形质量的影响规律。仿真结果表明:减小摩擦因数可有效降低发动机横梁壁厚减薄程度,轴向补料路径对其厚度分布影响较为明显。 相似文献
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