In this study, in order of to reflect the mold deformation in the injection molding process to design of mold, the mold deformation was analyzed by performing flow and structural analysis. The 5 inch LGP(light guide plate) mold, platen and tie bar were modeled and applied to the analysis. The result of melt pressure from flow analysis was extracted for use as boundary conditions acting on the mold surface in the structural analysis. In order to evaluate the accuracy of simulation analysis results, injection molding was performed under the process conditions of simulation. As a results, the mold deformation during injection molding tends to be similar that of injection pressure, and it is confirmed that it shows the behavior and properties of melt resins. Compared with the simulation and experiment, the error of the maximum mold deformation in the injection phase was 4.20%.
A press which has a 20 percent share in machine tools is one of the production facilities. The press has been used to make a hole or to bend metal plates. However, recently hydraulic press is used to reinforce competitiveness of the manufacturing industry. The press by using metal powder makes products without additional process while conventional processing machine makes products after removing unnecessary parts. In this way, large quantity of products can be produced in a short time. Researches to manufacture products by the press have been proceeding after 1970. In this study, structure and displacement analysis for punch used as the component for hydraulic press was investigated and structural stability was identified based on the results
In this study, analysis on the stiffness of the headrest, the stiffness of front-rear load and the torsion of cushion frame was performed using finite element method in order to investigate the properties of the stress-deformation by material characteristics according to the test requirements of FMVSS (Federal Motor Vehicle Safety Standard). The results are shown that AZ31 (Mg alloy) and A365 (Al alloy) with low modulus of elasticity and density have higher strain rate than steel in terms of stress-deformation and meet the standards for safety within 108 mm of the maximum amount of deformation. Considering it’s safety and durability, however, the selection of AZ31 for light weight seems difficult to gain the reliability because it causes an excessive deformation, and therefore it is not expected to be used for recliner where stress is concentrated and also the bracket linking rail and cushion frame.
The air blowers for fuel cell electric vehicle usually have big difference between inlet and outlet pressure. When the casing of the air blowers is designed, the stress analysis is required. (Approximately Inlet pressure is 0.5bar and outlet pressure is 2bar.) Gap distance between the casing and the impeller is 0.3mm. Therefore, if the amount of maximum deformation of casing is larger than 0.3mm, impeller crashed the casing. In order to avoid crashing, both the thickness and number of rims are changed and carried out simulations on each cases.
The through-thickness variations of strain and microstructure during high-speed hot rolled 5052 aluminum alloy sheet were investigated. The specimens were rolled at temperature ranges from 410 to 560˚C at a rolling speed of 15 m/s without lubrication and quenched into water at an interval of 30 ms after rolling. The redundant shear strain induced by high friction between rolls and the aluminum sheet was increased largely beneath the surface at a rolling reduction above 50%. Dynamic recrystallization occurred in the surface regions of the specimen rolled under conditions of high temperatures or high rolling reductions.
The through-thickness variations of strain and microstructure of high-speed hot rolled 1050 pure aluminum sheet were investigated. The specimens of 1050 aluminum were rolled at temperatures ranging from 410 to 560˚C at a rolling speed of 15 m/s without lubrication and quenched in water at an interval of 30ms after rolling. The redundant shear strain induced by high friction between rolls and the aluminum sheet was increased largely beneath the surface at a rolling reduction above 50%. Recrystallization occurred in the surface regions of the specimen rolled to reduction of 65% at 510˚C, while only recovery occurred in the other regions.
In a total hip arthroplasty, the artificial hip joint is composed of an acetabular cup and a femoral head. To minimize the wear of the joint, the bearing surface should be precisely spherical. There were concerns that the press-fitting of the acetabular cup to the pelvis may cause the deformation of the cup and accelerate the wear of the joint, but its in-vivo measurement was challenging. In this paper, 3 dimensional finite element(FE) models of a pelvis and acetabular cups of Metasul 50mm and Pinnacle 50-60mm cups were used to simulate the deformation of the acetabular cups. For Metasul cups, the change of inner radius with respect to the location and the maximum shrinkage of the inner radius were found. For the Pinnacle cups, maximum change of the outer diameter were found and compared with the literature. FE model showed that the maximum shrinkage of the inner radius of the Metasul cup was 23μm (1.0mm press-fit, Bone stiffness 17GPa case). The shrinkage occurred mainly on the anterior and posterior side of rim of the cup, and the amount was proportional to the press-fit amount. The diametric change of the Pinnacle cup was 0.16mm on average, which was in same range of the clinically reported value. In conclusion, under the normal condition the reduction of the inner radius of the Metasul cup was too small to cause the jamming or the excessive wear.
All the structures include initial imperfections that can affect the structural behavior and stability, particularly during construction. Therefore, for a concrete beam with an initial lateral deformation, creep analysis was performed to evaluate the influence of the initial imperfection on the creep deformation of the beam in the both vertical and lateral directions.