Three-dimensional simulation of staggered flow forming process

Recent years laser-assisted manufacturing techniques are increasingly the focus of the automotive and aerospace industry due to cost price, low energy efficiency and safety. Among these techniques is laser-assisted flow forming process that combines laser beam technology with conventional flow forming process. During forming the material undergoes a rapidly heating and cooling cycles with the irradiative action of the laser beam, which is quite different from the traditional process. A transient three-dimensional model was developed to investigate the influence of laser irradiation on the forming process, in which a user-defined function was created to overcome the problem of a moving Gaussian heating source. The result indicates that a ring-shaped temperature field is acquired when the heating source scans workpiece along a thread; the deformation area on the workpiece during forming is extensively and continuously heated by intense laser radiation and the thermally induced loss of material strength significantly increases the formability concerning the achievable material reduction rate and tool service life; the possibility of accuracy improvement by laser assistance has been investigated and an accuracy error decreases 10%-28.5%.

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Three Dimensional Simulation of Air Bleed Duct under Deep Drawing of Ti 6Al-6V-2SN

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.766-767.1050 ◽

2015 ◽

Vol 766-767 ◽

pp. 1050-1054

Author(s):

P. Gunasekar

Keyword(s):

High Pressure ◽

Deep Drawing ◽

Three Dimensional ◽

Extreme Temperature ◽

Cost Effective ◽

Maintenance Cost ◽

Climate Control ◽

Forming Process ◽

Long Time ◽

Dimensional Simulation

Deep drawing is the compression-tension forming process which has been around for a long time. This is a cheap and cost effective process. This paper investigates the manufacturing of the air bleed duct under deep drawing with the velocity of 7 inches/second. Bleed air is compressed air taken from aircraft turbine engines for cabin climate control and systems such as de-icing equipment and also used in after burners. Bleed air duct used to operate the control of air flow to the cabin and powerplant. Bleed air possesses high temperature and high pressure, hence the quality of the duct should be strong enough to withstand them. In general air bleed duct made of titanium alloys under forming process with low strength, which causes the failure and replacement of air bleed duct when they expose to extreme temperature cases. The deep forming process will increase the strength of the bleed duct which reduces the replacement of air duct periodically and reduces the maintenance cost of the aircraft. In addition this paper provides the stress and strain energy data in order to understand the mechanical behavior of titanium alloy when they undergo high pressure blank process.

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Three Dimensional Finite Element Analysis of Staggered Backward Flow Forming Process

Volume 1: Processing ◽

10.1115/msec2013-1219 ◽

2013 ◽

Author(s):

Hemant Shinde ◽

Pushkar Mahajan ◽

Ramesh Singh ◽

K. Narasimhan

Keyword(s):

Finite Element ◽

Three Dimensional ◽

Process Conditions ◽

State Variables ◽

Forming Process ◽

Flow Forming ◽

Element Analysis ◽

Cold Forming ◽

Cylindrical Workpiece ◽

Backward Flow Forming

Flow forming is one of the cold forming processes which is mainly used to produce thin-walled high-precision tubular components. A three dimensional coupled-field thermo-mechanical finite element model for staggered three-roller backward flow forming of a cylindrical workpiece of MDN-250 maraging steel has been developed using Abaqus/Explicit. In this model, the effect of tip radius of the rollers and friction between the rollers and the workpiece has been considered. The bottom of the workpiece is fixed in the axial direction so that diametral reduction and the axial elongation can be studied. Simulations have been carried out at different process conditions to study the state variables, such as stresses and strains obtained during the deformation. The model has been benchmarked with the experimental results for thickness reduction and the error in the thickness prediction is limited to 4%. The roll forces have been benchmarked against analytical formulation and a difference of 13–20% has been observed. The effect of flow forming process variables, such as feed rate and reduction ratio on the stress/strain distribution and roll forces have been studied. The results show that the roll forces increase at higher feed rates and higher reduction ratios whereas the equivalent strains increase at lower feed rates and higher reduction ratios. In addition, a parametric study has been conducted to study ovality, diametral growth, roll forces, stresses and strains as a function of process parameters.

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