Spinning-punch new technology for aluminum alloy plate-wheels forming
The aluminium alloy plate-wheels are a new kind of wheels with light-weight, energy-saving and environmental protection. Spinning is a conventional technology to form aluminium alloy plate-wheels, but the outline dimension and run-out of rolled lip in end face are difficult to meet the exacting requirements of wheels blueprint. So the new spinning-punch forming technology for aluminium alloy plate-wheels was researched and simulated. 3-D elastic-plastic finite element models were constructed and appropriate boundary conditions were given out. The results show that aluminium alloy plate-wheels with good quality can be formed by spinning-punch forming technology through controlling roller feed rate, roller'diameter, flanging times, and punching stroke, etc. And the relationships between spinning load and roller'diameter, rolled lip forming quality and flanging times are found.
An analysis of the forging processes for 6061 aluminum-alloy wheels
Abstract The metal forming processes of aluminum-alloy wheel forging at elevated temperatures are analyzed by the finite element method. A coupled thermo-mechanical model for the analysis of plastic deformation and heat transfer is adapted in the finite element formulation. In order to consider the strain-rate effects on material properties and the flow stress dependence on temperatures, the rigid visco-plasticity is applied to the simulation. Several process conditions were applied to the simulation such as punch speed, rim thickness, and the depth of die cavity. Experiment for a simplified small-scale model is carried out and compared with the simulation in terms of forging load to verify the validity of the formulation adapted in this study. Then, various processes with full-scale model for a 6061 aluminum-alloy wheel are simulated. Material flow, pressure distributions exerted on the die wall, temperature distributions and forging loads are summarized as basic data for process design and selection of a proper press equipment.
Constitutional Identity in the EU— A Shield or a Sword?
This Article consists of five sections. In the first section, it describes why identity questions matter, particularly in Europe. In the second section, the Article tackles the issue of multiple structural ambiguities affecting the concept of constitutional identity in the European constitutional vocabulary. In the third section, the Article explores trends concerning the use of constitutional identity in the European legal discourse and practice, including the development of alternative interpretations and applications of the notion of constitutional identities in the Member States. The fourth section of the Article combines the analytical accounts outlined in the second section with the trends identified in the third section, contending that different conceptions and applications of constitutional identity have varying effects on the European composite constitutional adjudication system and that the institutional and procedural framework should be calibrated accordingly. The final section of this Article draws some conclusions.