Simulation of Multi-step Tube Hot Gas Forming Process of a UHSS Torsion Beam

Hot metal gas forming (HMGF) is a desirable way for the automotive industry to produce complex metallic parts with poor formability, such as aluminum alloys. A simple hot gas forming method was developed to form aluminum alloy tubes using flame heating. An aluminum alloy tube was heated by a flame torch while the tube was rotated and compressed using a lathe machine and simultaneously pressurized with a constant air pressure. The effects of the internal pressure and axial feeding on expansion and wall thickness distribution were examined. The results showed that the proposed gas forming method was effective for forming aluminum alloy tubes. It was also indicated that axial feeding is a vital parameter to prevent reductions in wall thickness by supplying the material flow during the forming process.

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Investigation on precision and performance for hot gas forming of thin-walled components of Ti2AlNb-based alloy

MATEC Web of Conferences ◽

10.1051/matecconf/201819007001 ◽

2018 ◽

Vol 190 ◽

pp. 07001

Author(s):

Xueyan Jiao ◽

Zhiqiang Liu ◽

Yong Wu ◽

Gang Liu

Keyword(s):

Process Parameters ◽

Microstructure Evolution ◽

Element Model ◽

Parameters Optimization ◽

Forming Process ◽

Performance Control ◽

Hot Gas ◽

Thin Walled ◽

And Performance ◽

Hot Gas Forming

Ti2AlNb-based alloys have received considerable attention as potential materials to replace the nickel alloy at 600-750 °C, depending on their advantages of high specific strength, good corrosion and oxidation resistance. To realize the precision and performance control for Ti2AlNb-based alloy thin-walled components, the microstructure evolution was analyzed for setting up the unified viscoplastic constitutive equations based on the physical variables and simulating the forming process coupled between the deformation and the microstructure evolution. Through the finite element model with coupling of microstructure and mechanical parameters, the microstructure evolution and shape fabricating can be predicted at the same time, to provide the basis for the process parameters optimization and performance control. With the reasonable process parameters for hot gas forming of Ti2AlNb thin-walled components, the forming precision and performance can be controlled effectively.

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Thickness and Microstructure Analysis on Hot Gas Bulged Cup-Shaped Parts of Ti-22Al-24.5Nb-0.5Mo

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.716.138 ◽

2016 ◽

Vol 716 ◽

pp. 138-143

Author(s):

Yong Wu ◽

Gang Liu ◽

Zhi Qiang Liu ◽

Bei Bei Kong

Keyword(s):

Mechanical Properties ◽

Cylindrical Part ◽

Outer Diameter ◽

Jet Engines ◽

Forming Process ◽

Complex Phase ◽

Hot Gas ◽

Cylindrical Parts ◽

Application Potential ◽

Hot Gas Forming

Ti2AlNb based alloy has been paid more and more attention in recent years because of their high application potential in jet engines for good mechanical properties at high temperature. However, the control of microstructure and mechanical properties for components in sheet metal forming is very difficult because the complex phase transformation. In this paper, a cylindrical part was produced by hot gas forming and the formability of a Ti-22Al-24.5Nb-0.5Mo sheet with thickness of 2mm was studied at 985°C. It is found that the parts could be formed with small bottom-corner radius of 4mm with outer diameter of 60mm and the depth of 20mm. The strain distribution and thinning ratio of the parts were analyzed. The maximum thinning ratio was 56.3% near to the small corner. The microstructures of the original blank and the cylindrical parts were observed by optical microscopic (OM). It is found that the orthorhombic (O) phase and α2 phase significantly reduced during the forming process. On the other hand, at different position of the parts, different microstructures appear because of different strain values.

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Improvement of Mechanical Properties and Forming Efficiency during Hot Gas Forming of CFRP Curved Surface Components

Materials ◽

10.3390/ma14185316 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5316

Author(s):

Yizhe Chen ◽

Yi Lin ◽

Hui Wang ◽

Zhiwen Liu ◽

Lin Hua

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Gas Pressure ◽

Curved Surface ◽

Cover Plate ◽

Forming Process ◽

Hot Gas ◽

New Energy ◽

Forming Efficiency ◽

Hot Gas Forming

Carbon fiber reinforced plastics (CFRP) are widely used in aerospace and new energy vehicles due to their high specific strength and flexible design ability. At present, the traditional forming process of CFRP curved surface components has problems of low mechanical properties and long processing time. In this paper, a new method of hot gas forming was proposed to obtain CFRP components. By applying high temperature and high-pressure gas on one side of CFRP, the material was forced to deform and solidify at the same time. A special device for hot gas forming was designed and developed. The curing behavior and mechanical properties of original CFRP plates were studied. The main defects and the corresponding control methods of hot gas forming parts were analyzed by forming spherical parts, and the feasibility of the hot gas forming process was verified. Taking the battery cover plate of a new energy vehicle as the research object, the influence of forming temperature, gas pressure, pressurization rate and other process parameters on the mechanical properties of complex CFRP components were analyzed. The mechanism of both strength and efficiency improvement was analyzed. The results showed that with the increasing of gas pressure, the tensile strength and forming efficiency of the CFRP curved components were improved obviously. Under reasonable forming parameters, the tensile strength of the obtained parts was increased by 37%, and the forming efficiency was increased by 58%. The fiber bundles were distributed more evenly and compactly under the hot gas forming. This showed that the use of hot gas forming had good potential in the preparation of high-performance CFRP parts, which was helpful to improve the processing efficiency and forming quality of CFRP curved parts in the aerospace and new energy automotive fields.

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Design of Hydraulic Bulging Die for Automobile Torsion Beam and Optimization of Forming Process Parameters

Advances in Materials Science and Engineering ◽

10.1155/2021/9982515 ◽

2021 ◽

Vol 2021 ◽

pp. 1-18

Author(s):

Kefan Yang ◽

Youmin Wang ◽

Kexun Fu

Keyword(s):

Friction Coefficient ◽

Process Parameters ◽

Orthogonal Experiment ◽

Die Design ◽

Molding Pressure ◽

Hydraulic Pressure ◽

Forming Process ◽

Torsion Beam ◽

Supporting Pressure ◽

Hydraulic Bulging

The hydraulic bulging technology of tubes can provide hollow parts with special-shaped cross sections. Its manufacturing process can effectively improve material utilization and product accuracy and reduce the number and cost of molds. However, the hydraulic bulging process of parts is very complicated. The size of the tube blank, the design of the loading route, and the forming process parameters will have an effect on the molding quality. Closed tubular torsion automobile beam is considered as the research object to study hydraulic bulging die design and optimize forming process parameters. CATIA software is used to design torsion beam product structure and hydraulic bulging die. AMESim software is employed to design hydraulic synchronous control system for cylinders on both sides of the hydraulic bulging die. Mathematical control model is established and verified in Simulink software. DYNAFORM software is applied to conduct numerical simulation of hydraulic expansion. The supporting pressure, molding pressure, friction coefficient, and feeding quantity are taken as orthogonal experiment level factors. Maximum thinning and maximum thickening rates are taken as hydraulic pressure expansion evaluation indexes to complete the orthogonal experiments. Main molding process parameters are analyzed via orthogonal experiment results and optimized by employing the Taguchi method. Optimal hydraulic bulging parameters are obtained as follows: supporting pressure of 20 MPa, molding pressure of 150 MPa, feeding quantity of 25 mm, and friction coefficient of 0.075. Simulation analysis results indicate that the maximum thinning rate is equal to 9.013%, while the maximum thickening rate is equal to 16.523%. Finally, the design of hydraulic bulging die for torsion beam was completed, and its forming process parameters were optimized.

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