Study on the Characteristics of Laser Forming of TC4 Titanium Alloy Sheet Metal by Thermal Stress

The thermo-stress sizing is a technology that enables sheet metal part using high elastic material such as titanium alloy to eliminate spring-back and distortion. The paper expounds and proves the principle of fixing shape of thermal stress sizing, that is, they are synthetic effects of materia1 softening and stress relaxation in short time．Then the theoretical rule of hot sizing for bending spring-back is established by this principle．On the basis of principle of the thermo-stress sizing, relevant replication experiment is implemented. The results show quantitatively effects of main factors, such as material property, part geometry, temperature and time for the rule of hot sizing． The theoretical values of spring-back in the process of hot sizing are in good agreement with that of experiments. They may be used to estimate technological parameters of thermal stress sizing．In addition thermo-mechanical characteristics under standard temperatures of forming or sizing and the experimental curves of thermo-stress sizing for Ti-6Al-4V and Ti-2A1-1.5M n are given．

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Numerical Simulation and Experiment of Electrically-Assisted Incremental Forming of Thin TC4 Titanium Alloy Sheet

Materials ◽

10.3390/ma13061335 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1335

Author(s):

Bo Jiang ◽

Wenbing Yang ◽

Ziyang Zhang ◽

Xifeng Li ◽

Xueping Ren ◽

...

Keyword(s):

Titanium Alloy ◽

Incremental Forming ◽

Simulation Method ◽

Alloy Sheet ◽

Cycle Period ◽

Forming Process ◽

Mechanical Coupling ◽

Tc4 Titanium Alloy ◽

Electrically Assisted ◽

Alloy Part

In order to integrally manufacture the large TC4 titanium alloy part, an electrically-assisted incremental forming process is cleverly proposed to solve the traditional hot forming disadvantages of expensive heating furnaces and long cycle period. The two-step simulation method including thermal-electricity coupling simulation and thermo-mechanical coupling simulation was selected to predict the temperature variations and the sheet deformation behaviors. The electrically-assisted incremental forming experiment of thin TC4 titanium alloy sheet was performed. The highest prediction error is 6% for springback angles. The thrice forming at 10.9 A/mm2 satisfies the precision requirement of the designed part. Therefore, the two-step simulation method can effectively calculate the electrically-assisted incremental process. The electrically-assisted incremental forming technique is very promising for the integral producing large titanium alloy part.

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Determination of FLD for Ti-6Al-4V Titanium Alloy Sheet

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.687.171 ◽

2016 ◽

Vol 687 ◽

pp. 171-178

Author(s):

Piotr Lacki

Keyword(s):

Titanium Alloy ◽

Numerical Simulations ◽

Real Time ◽

Sheet Metal ◽

Sheet Metal Forming ◽

Metal Forming ◽

Forming Limit Diagram ◽

Alloy Sheet ◽

Forming Limit

Ti-6Al-4V is the most widely applied titanium alloy in technology and medicine due its good mechanical properties combined with low density and good corrosion resistance. However, poor technological and tribological properties make it very difficult to process, including the problems with sheet-metal forming. The best way to evaluate sheet drawability is to use Forming Limit Diagram (FLD), which represents a line at which failure occurs. FLD allows for determination of critical forming areas.The FLDs can be determined both theoretically and experimentally. Recently, special optical strain measurement systems have been used to determine FLDs.In this study, material deformation was measured with the Aramis system that allows for real-time observation of displacements of the stochastic points applied to the surface using a colour spray. The FLD was determined for Ti-6Al-4V titanium alloy sheet with thickness of 0.8 mm. In order to obtain a complete FLD, a set of 6 samples with different geometries underwent plastic deformation in stretch forming i.e. in the Erichsen cupping test until the appearance of fracture.The real-time results obtained from the ARAMIS software for multiple measurement positions from the test specimen surface were compared with numerical simulations of the cupping tests. The numerical simulations were performed using the PamStamp 2G v2012 software dedicated for analysis of sheet-metal forming processes. PamStamp 2G is based on the Finite Element method (FEM). The major and minor strains were analysed. The effect of friction conditions on strain distribution was also taken into consideration

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Optimization of Process Parameters of Thin Aluminum-lithium Alloy Sheet Metal Laser Forming

Applied laser ◽

10.3788/al20103005.0399 ◽

2010 ◽

Vol 30 (5) ◽

pp. 399-403

Author(s):

姜敏凤 Jiang Minfeng ◽

丁磊 Ding Lei ◽

王霄 Wang Xiao ◽

刘会霞 Liu Huixia

Keyword(s):

Sheet Metal ◽

Process Parameters ◽

Alloy Sheet ◽

Laser Forming ◽

Lithium Alloy ◽

Aluminum Lithium Alloy ◽

Optimization Of Process Parameters ◽

Thin Aluminum ◽

Aluminum Lithium

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Experimental Study of Thin Aluminum-Lithium Alloy Sheet Metal Laser Forming with Semiconductor Laser

Chinese Journal of Lasers ◽

10.3788/cjl20103708.2143 ◽

2010 ◽

Vol 37 (8) ◽

pp. 2143-2148 ◽

Cited By ~ 3

Author(s):

丁磊 Ding Lei ◽

刘会霞 Liu Huixia ◽

王鹤军 Wang Hejun ◽

王霄 Wang Xiao

Keyword(s):

Experimental Study ◽

Semiconductor Laser ◽

Sheet Metal ◽

Alloy Sheet ◽

Laser Forming ◽

Lithium Alloy ◽

Aluminum Lithium Alloy ◽

Thin Aluminum ◽

Aluminum Lithium

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Forming Of Spherical Titanium Cups From Circular Blanks With Cutouts On The Perimeter

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0214 ◽

2015 ◽

Vol 60 (2) ◽

pp. 829-834 ◽

Cited By ~ 1

Author(s):

P. Lacki ◽

J. Adamus ◽

W. Więckowski ◽

J. Winowiecka

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Titanium Alloy ◽

Sheet Metal ◽

Strain Distribution ◽

High Strength ◽

Alloy Sheet ◽

System Software ◽

Cold Forming ◽

Ti6al4v Titanium Alloy

Abstract Despite substantial demand for drawn parts made of high-strength sheet metal (including titanium alloys) observed in the modern industry, particularly automotive and aviation, their application remains insignificant. This results from the fact that such sheet metal shows poor plasticity and its cold-forming is almost impossible. Low drawability makes it impossible to obtain even such simple shapes as spherical cups. The authors of this study developed circular sheet-metal blanks with cutouts on their perimeter. The blanks allow for cold forming of spherical cups from Ti6Al4V titanium alloy sheet metal using conventional rigid tools. The cutouts proposed in the study affect plastic strain distribution, which in turn leads to an increase in forming depth by about 30%. The numerical analysis, performed using the PamStamp 2G System software based on finite element method, was verified experimentally.

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