Papers by Keyword: Formability

Abstract: Formability and mechanical properties of metal sheets are related to on their textures. It has been studied to improve the formability and change the texture of the AA 3003 Al alloy sheets after asymmetric rolling. Asymmetrically rolled Al sheets are shown the high intensity of the distorted cube texture, {001}, distorted rotated cube texture, {001}, weak γ-fiber, ND//, {123}, {120} and {120} components. After the asymmetrically rolled AA 3003 Al alloy sheets, the plastic strain ratios of the asymmetrically rolled Al alloy sheets were about 1.7 times higher than those of the initial Al sheets. The variation of plastic strain ratios of the asymmetrically rolled Al alloy sheets could be related to the change of texture components through asymmetrical rolling in AA 3003 Al sheet.

Abstract: Texture of Al alloy is affected to the formability and mechanical properties. In this paper, it was studied that the change of texture and formability of AA 1050 Al alloy sheets which were asymmetrically rolled. Asymmetrically rolled Al sheets showed that the distorted rotated cube texture, {001}, γ-fiber, ND// and {120} and {120} components were increased. The change of texture components after the asymmetrical rolling could be affected to the variation of plastic strain ratios of the asymmetrically rolled AA 1050 Al alloy sheets.

Abstract: The texture, microstructure, plastic strain ratio r value, elongation, strain hardening index n, the value of cupping test I_E, and the correlation between r value and the other formability indices of two automotive aluminum alloys sheet 6016 and 6181, and commercial pure aluminum sheet were investigated. The results showed that the recrystallization textures of three aluminum alloys sheet are similar to each other, which mainly contain cube component. However, the r and n value, elongation, and I_E of three aluminum alloys sheet are different from each other evidently, and there is no correlation between texture and r value, and the other formability indices except the n value. The large quantity of second-phase particles in the aluminum alloy matrix has very important effect on both the r value and the formability of aluminum alloy sheet.

Abstract: Aimed at Zr44Ti11Cu10Ni10Be25 amorphous alloy and based on POLYFLOW software, studies the influence of die inlet diameter, blowing pressure and die transition fillet on the blow molding performance of tube blank systemly, and raises a new evaluation index to evaluate the formability of amorphous tube blank, limit height to diameter ratio (LHTDR) . The simulation results indicate that the forming limit of tube blank can be multiple improved with the decrease of die inlet diameter, blowing pressure has a significant effect on the forming limit which can be improved by decreasing the pressure, and the larger of the die transition fillet the higher of the forming limit in certain range. Finally, a set of reasonable process parameters is given which has great significance for guiding the formulation of blow molding process scheme.

Abstract: Nowadays, the tailor-welded blanks (TWBs) technology has been developing very rapidly in China. The quality of tailor-welded blanks becomes more and more important for the stable manufacturing of automotive panels. therefore, it’s very necessary to find out the key factors that influence the forming performance of tailor-welded blanks. This paper experimentally studies the effect of weld line direction on drawing performance. The tailor-welded blanks with the same material pair were used in the experiment, in which the weld line is straight and forms a certain angle with drawing force. The drawing tests were done with the different angles and values of relative position. The results show that the forming performance is related to the relative position of weld line and the angle between weld line and drawing force.

Abstract: Light and highly resistant, magnesium has been more and more included into alloys composition, especially in automotive and electronic devices. Usual automotive applications for magnesium alloys are gearbox, cylinder head covers and other types of covers, when electronic industry uses this alloys for mobile computers and mobile phones frames (chassis). However casting is still the first production process for magnesium application, press forming is considered as having significant potential. Yet, influences of many key parameters are not clearly known. In this report, sheets of AZ31 magnesium alloy were submit to deep drawing tests to investigate the influence of temperature, lubricant, blank holding pressure and speed. As a result, an appropriate lubricant was selected out of a set of potentially interesting lubricants selected with respect to their announced properties. Deep drawing tests also enlighten the poor formability of AZ31 even at 160°C and an apparent optimum formability temperature at 200°C. Other tests and controls, like thickness profile, were also performed to complete knowledge of AZ31 properties.

Abstract: Incremental Sheet Forming (ISF) is a promising sheet-metal-forming technology which is drawing more and more researchers’ attention due to its flexibility of manufacturing three-dimensional products at a relatively low cost for rapid prototyping and small-batch production. This paper is focused on the thickness distribution and the forming strategy analysis for two point incremental forming with a male die. The analyzed benchmark is half a torus which is generated by revolving a semi-circle. Such a part is hardly able to be formed by single point incremental forming because its slope varies from 0 degree to 90 degrees. In terms of the varying slope, the variant of sine’s law is derived to give an approximate prediction of the thickness distribution from an analytical perspective. In addition, a multi-stage forming strategy is proposed in order to form the part successfully. In particular, a keying operation is implemented carefully in order to avoid twist phenomenon and achieve good dimensional accuracy.

Abstract: Multi-layered biaxial weft knitted fabrics has excellent mechanical properties and formability. The performances of multi-layered biaxial weft knitted fabrics were compared with multi-axial warp knitted fabrics and plain weave fabrics to highlight the advantages of this novel fibrous assembly. The manufacturing method and applications of the developed novel fabrics were illustrated in details.

Abstract: Forming limit curve (FLC) is an important tool for assessing formability of steel metal. It is commonly obtained from experiment, theoretical calculation and finite element method (FEM) simulation. In this study, the FLC of a seamed tube hydroforming is established by combining the failure criterion of strain increment ratio and FEM simulation. The numerical method is verified by tube bulge tests. Then the sensitivity studies are carried out to evaluate the effect of the geometrical features of seamed tube on its formability by numerical approach. Results show that the changes of the formability with the geometrical features of a seamed tube.

Abstract: The feasibility of using modern computers in manufacturing has evolved an era in the development of several new sheet metal forming process. The concept of profile forming technique has been investigated for production of sheet metal components. Profile forming is a very promising technology to manufacture sheet metal producs by CNC controlled movement with simple forming tool. Profile forming was developed as a flexible, alternative manufacturing method to effectively prototype stampings and produce in small lots. Cylindrical Cup is formed on Aluminium sheet of grade Al 3003 (O) without using punch and die. Formability of material, maximum wall angle, Surface roughness, thinning of sheet and Microstructural characteristics of Aluminium sheet are studied.