Papers by Keyword: Rolling Direction

Abstract: Magnesium alloys were being increasingly considered for sheet forming applications because of their low density and high strength. Therefore, the main areas of research focused on the deformation mechanisms, improving ductility, and possible forming applications [1]. Published results on deformability and springback prediction of magnesium alloy stripes are minimal. The rolling direction of the materials with respect to the deformation direction can greatly influence on springback as well as formability. Though novel approaches relating to the formality of magnesium alloy stripes are available, the change of springback due to the characteristic of each process should be verified by finite element method [2]. In this study, the magnesium alloy strips having the thickness of 1mm, are used to investigate springback characteristics in U-shape bending. The Dynaform 5.8 software was used to simulate the forming process, in which the rolling directions of the material vary with respect to the main deformation axis. There are three different cases: RD0^o, RD45^o and RD90^o. The springback phenomenon is simulated using the same software, but a different module. The following aspects stand out from the simulation tests of the influence of rolling direction on springback parameters: the material rolling direction perpendicular to the deformation direction (0^o) leads to reduction of springback intensity; the thickness of the material in case of RD0^o is reduced in comparison with the one of RD90^o. It can be considered that the results generated by the analysis of springback phenomenon using finite element method are sufficiently accurate and can be considered valid.

Abstract: rolling/plowing-extrusion is a new method for fabricating outside 3D integral fin stainless steel tube.The effect was investigated about Rolling and plowing-extrusion affect the finned forming and structure. In this study, the rolling depth and direction were analyzed. The results are shown that The rolling processing play an important role to finned structure.When the rolling depth is 1.5mm, and other parameters are reasonable by right spiral groove, the optimal fins were obtained.

Abstract: The manufacturing of machine components with sustainable and innovative methods is an interesting topic for research. Gears are some components which have complexity in both design and production technology. Therefore applying innovative methods on gear manufacturing can be of interest to industry. One of the most promising production methods for gear wheels is Gear Rolling. The gear wheel is formed during a certain rolling process from a cylindrical blank into the final designed shape. The process of gear rolling with rotational gears is progressing by running several rolling cycles with one, or two dies in contact with a work-piece. A specified rotational speed and radial feed speed is applied to the dies in order to form the required geometry on the blank. In this paper, the authors have simulated the process with the finite element code, DEFORM 3D. Especially the effects of reversal cycles on final gear wheel geometry have been evaluated from the simulations. Different settings for the rotation direction of the dies have been used and the effects are evaluated with specific quality criteria.

Abstract: In this research, it has been carried out the development of a strength analytical method of a thin-walled steel square pipe (Square Hollow Section/SHS) affected by the interaction of concentrated-compressive load and bending moment then it verified by experimental approach. The experimental approach was consisted of measuring a basic material property and the strength of the investigated SHS pipe. The basic material property identified parallel to rolling direction (0^o) and perpendicular to rolling direction (90^o). The analytical data obtained from cut-off strength method is generally scattered within the acceptable limits of ± 20 % and tends to be in unconservative region. The actual data measured from experiments shows that SHS beam with t = 0.6 mm and longitudinal axis parallel to the rolling direction of base material has higher strength compared to the one of the SHS beam with t= 0.6 mm and longitudinal axis perpendicular to the rolling direction, meanwhile the SHS beam with t= 1.2 mm is tends to be equal. This means that the rolling direction of base material can be considered to be a parameter in the strength design of a thin-walled SHS beam

Abstract: Stress measurement based on the change of ultrasonic surface wave has been accepted to find out residual or existing stress on material. This paper shows the effect of rolling direction and grain size of material on surface wave velocity and energy attenuation. Different grain and rolling direction of material type SS 400, S420 and A516 were selected to test its effect. Three grain sizes of each material were varied by normalizing process at three temperature range (no heating, 850°C, 980°C and 1160°C). Through transmission ultrasonic surface wave, frequencies 2.25 and 5 MHz, were applied and recorded the velocity and attenuation of the response. The results show that rolling direction and grain size slightly effect on attenuation of ultrasonic wave but unaffected on sound velocity. Its outcome was compared with the effect of the material coating.

Abstract: This paper shows that different materials have different quadratic functions, tensor function theory can make the function of history to represent the plastic strain, which can be a sheet metal pressing does uniaxial tensile test show that the plane of sheet metal, sheet metal specimen axis and the angle between the rolling direction changes, to the metal plastic strain ratio (R) along with the changes. To explain this phenomenon, the introduction of a quadratic yield function to describe the experimental results of some of the metal sheet. This paper shows that different materials have different quadratic functions, tensor function theory can make the function of history to represent the plastic strain, which can be a sheet metal pressing does not depend on the value of history.

Abstract: In this paper it is presented a study of the magnetic anisotropy of non-oriented and grain oriented Fe-Si strips with the surface area of 280 x 30 mm2. The measurements were performed with a unidirectional single strip tester on Fe-Si strips cut at angles of 0, 15, 30, 45, 60, 75, 90 with the rolling direction. For the representation of the magnetic field strength at constant magnetic flux density it was used a program that interpolated the experimental results. It was determined the hard and the easy axis of the materials and the influence of the frequency on the anisotropy of the materials.

Abstract: H beam welds along rolling and transverse direction were investigated with nondestructive testing, mechanical testing and microstructural analysis. Crack and fracture occurred, during guided bend testing, in the specimens welded along rolling direction between flanges of the H beams with higher S content although no defect was detected prior to the bend test. The fracture seemed to be lamellar tearing because of step-like fracture propagation and terrace and wall fracture appearance of the ruptured bend test specimen. On top of this, lamellar tear was already created in the base metal area near the HAZ before the bend test in microstructural analysis on the welds. It seems that lamellar tearing occurred in the specimens welded along rolling direction between flanges of the H beams with higher S content as cracks were formed and propagated into a ferrite phase region in α-γ band structure in combination with low ductility in transverse direction due to MnS inclusions elongated along rolling direction.

Abstract: The cross-ARB (C-ARB) process, which adopts cross rolling of the two stacked plates, has been performed up to seven cycles on a commercial purity 1050 aluminum alloy to obtain ultrafine grains with an average grain size of 0.7μm. Microstructural evolution of the C-ARB processed aluminum alloy was examined by a transmission electron microscopy as a function of process cycle number (accumulated plastic strain). Tensile property of the severely deformed Al alloy was also explored. Grain size of grains of the C-ARB processed alloy varied across thickness of the rolled plate. The size of grains at the top and bottom of the rolled plate converged to 0.65μm, while that of grains at the center of the plate increased with the number of ARB cycles. Tensile strength of the CARB processed 1050 Al alloy increased from 100MPa (as-received) to 160MPa. Tensile elongation varied with the number of cycles, but 15% of failure strain was measured from the 6-cycle C-ARB processed specimen. The variation of the elongation with the cycle number coincided exactly with the variation of grain size at the center of the processed plate.