Abstract: GF/Pb Complex Wire, as the key, characteristic component of a high-energy battery, is difficult to produce continuously for the fiberglass core’s liability to rupture in extruding. The research works, presented in this paper, show that this complex wire of brittle core can be successfully formed by the continuous side-way coaxial extrusion, using the die set specially designed, at a relative lower temperature and with a stable wire puling force.
Abstract: The aluminum profile can be formed into a complicated part such as 360º abnormity section circle parts that is difficult to be manufactured by other techniques. A new bending method was proposed for bending process. The push-bending principle, deformation procedure, curvature spring-back, section distortion and wrinkling are studied numerically. All cross-sections for the profile are provided a rather homogenous deformation degree. The curvature value of component and the distortion of section keep high consistence in push-bending process. The wrinkling tendency is reduced with increasing relative cross section thickness t/H and die radius R. The numerical model represents the observed response in the laboratory tests fairly well.
Abstract: With the entrance temperature at 300°C, cold mill rolling produced deformation texture transition from brass type to copper type in worked 85/15 α-brass. From the texture and TEM scale microstructure evidence, it is suggested that, rather than deformation twinning, recovery and easy cross slip favor in the deformation process, as the interior working temperature falls into the texture transition range proposed by Tranchant.
Abstract: This paper describes procedures and results obtained using 3D rigid plastic thermal-mechanical finite element model of wheel hub bearing rings. Numerical simulation for cold extrusion process is performed and metal flow characteristics, distribution of effective stress & temperature field and load-stroke curve are analyzed. Approach of tool wear prediction is also explored using Archard model . Process test revealed that numerical simulation provides theory basis and useful guidance for cold extrusion process specification and die design.
Abstract: T91/12Cr2MoWVTiB was bonded by transient liquid phase bonding process with different pressures, one commercial FeNiCrSiB was used as the interlayer. The microstructure and components distribution of the bonded joints were examined by optical microscope and scanning electron microscopic techniques. Furthermore, the properties of the joints were also tested. The results indicate that with the increase of the pressure – from 2 MPa to 6 MPa – the microstructures and mechanical properties were improved, and more similar to those base alloys. A theoretical study also revealed that the isothermal solidification complication time can be shorter, because the maximum liquid width was reduced with the existence of pressure.
Abstract: Backward ball spinning is applied to manufacturing thin-walled tubular part with longitudinal inner ribs. Rigid-plastic finite element method (FEM) is used to simulate and analyze backward ball spinning of thin-walled tubular part with longitudinal inner ribs. The fields of stress and strain in the deformation zone of the spun part are obtained by means of FEM. Finite element simulation results show that the deformation zone of the spun part is caused to be in a three-dimensional compressive stress state. The deformation zone in the inner rib is under the tensile strain in the radial and axial direction, and the compressive strain in the tangential direction. The wall deformation zone beside the inner rib is under the compressive strain in the radial direction, and the tensile strain in the axial and tangential direction. The three spinning force components all increase with the increase of the stroke of the ball. Furthermore, of all the three spinning force components, the radial force component is greater than the other two force components, and the tangential force component is minimum.
Abstract: It is difficult for the dynamic recrystallization to happen in Steel 26Cr2Ni4MoV, used to manufacture low-pressure steam turbine rotors generally. Static recrystallization was important in the fine crystals generation. Considering this, thermo-torsion method was adopted to investigate the spontaneous austenite recrystallization of steel 26Cr2Ni4MoV. Results show that even minute strain can promote the nucleation and growth of spontaneous austenite recrystallization dramatically, and the increase of temperature can also do so. The discovery can contribute to the realization of controlled forging.
Abstract: The intelligent sheet metal forming is a new technology. In this paper, take cone-shaped wall pieces and cone-box shaped part as an example , the key technologies in real-time monitoring, real-time identifying, real-time forecasting and real-time controlling are studied, which gradually is the theoretical basis for intelligent deep drawing control. The results can be more satisfactory when the artificial neural network is used in real-time identifying and real-time forecasting, when in the blank hold force control phase load curve is along critical rupture curve. In the course of this study the intelligent deep drawing experimental system is developed, in which the better identifying forecasting accuracy is showed. The research laid that the intelligent control method for deep drawing of a simple shape parts will be the successful sample of complex parts.
Abstract: Straight groove test is a widely-used formability test in Single Point Incremental Forming (SPIF). This test does not cover all the forming aspects of SPIF process, however. In order to ascertain its legitimacy, two new tests covering necessary SPIF aspects are devised. The FLC of an aluminum sheet is determined using the newly proposed and straight groove tests. It is found that the straight groove test shows much lower formability than the new tests. Therefore, the employment of newly devised test(s) is proposed for the determination of precise formability limits.
Abstract: The dimensional inaccuracy caused by springback is a major problem for most stamping applications. One of the most promising ways to solve this problem is to compensate it by means of appropriate tool shape modifications. In this paper, a new springback compensation method is introduced. A coefficient of curvature correction, which reflects the deviation of the experiment data and the analytical calculation data, is also proposed to redesign the tooling shape. This method was applied to a two-dimensional wavy-shaped part forming case for verification. The experiment results demonstrated that this method is efficient.