An Approach to Improve Thickness Uniformity of TA15 Tubular Part Formed by Gas Bulging Process

Liu, Gang; Wang, Ke Huan; Xu, Yang; Wang, Bin; Shi, Yuan

doi:10.4028/www.scientific.net/amr.712-715.651

Cited by 13 publications

(8 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…He [ 12 ] measured the formability of TA2 pure titanium at different temperatures and determined the best forming parameters, the results showed that a good formability could be attained at the proper temperature, at which the uniform elongation has the biggest value, but not the total elongation with necking. Liu [ 13 ] set up an HPPF device with a maximum pressure of 70 MPa, and conducted forming experiments of a TA15 Ti-alloy component with an irregular cross section, at temperatures of 800–850 °C.…”

Section: Introductionmentioning

confidence: 99%

High Pressure Pneumatic Forming of Ti-3Al-2.5V Titanium Tubes in a Square Cross-Sectional Die

et al. 2014

Self Cite

View full text Add to dashboard Cite

Abstract:A new high strain rate forming process for titanium alloys is presented and named High Pressure Pneumatic Forming (HPPF), which might be applicable to form certain tubular components with irregular cross sections with high efficiency, both with respect to energy cost and time consumption. HPPF experiments were performed on Ti-3Al-2.5V titanium alloy tubes using a square cross-sectional die with a small corner radius. The effects of forming of pressure and temperature on the corner filling were investigated and the thickness distributions after the HPPF processes at various pressure levels are discussed. At the same time, the stress state, strain and strain rate distribution during the HPPF process were numerically analyzed by the finite element method. Microstructure evolution of the formed tubes was also analyzed by using electron back scattering diffraction (EBSD). Because of different stress states, the strain and strain rate are very different at different areas of the tube during the corner filling process, and consequently the microstructure of the formed component is affected to some degree. The results verified that HPPF is a potential technology to form titanium tubular components with complicated geometrical features with high efficiency. OPEN ACCESSMaterials 2014, 7 5993 Keywords: high pressure pneumatic forming (HPPF); corner filling; strain rate sensitivity; electron back scattering diffraction (EBSD)

show abstract

Section: Introductionmentioning

confidence: 99%

High Pressure Pneumatic Forming of Ti-3Al-2.5V Titanium Tubes in a Square Cross-Sectional Die

et al. 2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…Based on the above discussions and previous research achievements on high pressure tube gas forming of Ti-alloy components [24][25][26], the deforming behavior of Ti-3Al-2.5 V tubular components with 50 % expansion ratio was investigated by considering the advantages of hydroforming and warm processing. To obtain uniform thickness distribution for this kind of hard-to-deform alloy, a two-stage loading path during deforming process was well designed.…”

Section: Introductionmentioning

confidence: 99%

Effect of feeding length on deforming behavior of Ti-3Al-2.5 V tubular components prepared by tube gas forming at elevated temperature

Liu

Wang

et al. 2015

Int J Adv Manuf Technol

Self Cite

View full text Add to dashboard Cite

In order to investigate the deforming behavior of the tubular components with a large expansion ratio fabricated by tube gas forming technique, the Ti-3Al-2.5 V tubular components with 50 % expansion ratio were studied under the forming conditions of internal pressure and axial feeding at 800°C. Through thickness measurements, EBSD and tensile tests, the effects of axial feeding on deforming behaviors, such as thickness distribution, microstructure, and mechanical properties of Ti-3Al-2.5 V tubular components, were investigated in details. The results showed that the average thinning ratio of the bulging area could be reduced significantly and the thickness distribution of the workpiece was more uniform with increasing of the feeding. Feeding length influenced the microstructure and strength of components. When the axial feeding ratio (actual feeding length/theoretical feeding length) was 56 %, the component had even higher tensile strength than the original tube because of the grain refinement. If the axial feeding was excessive large, the grain size became adversely coarser, which in turn reduced the tensile strength. These investigations illustrated that tube gas forming under high pressure had potential for fabricating complicated shaped titanium alloy tubular components by reasonably designing and controlling the deforming process.

show abstract

“…Liu et al presented a HPPF process based on QPF, HMGF and hydroforming [15]. With the maximum pressure of 30 MPa, they also successfully formed Ti-alloy components with irregular cross-sections and square cross-sections at 850°C [15,16].…”

Section: Introductionmentioning

confidence: 99%

Effects of flow stress behaviour, pressure loading path and temperature variation on high-pressure pneumatic forming of Ti-3Al-2.5V tubes

Liu

Wang

Dang

et al. 2015

Int J Adv Manuf Technol

Self Cite

View full text Add to dashboard Cite

High-pressure pneumatic forming (HPPF) is an internal high-pressure forming process at elevated temperatures, which is based on quick plastic forming (QPF), hot metal gas forming (HMGF) and hydroforming. In this study, the HPPF experiments were performed on Ti-3Al-2.5V tubes using a square cross-sectional die at higher pressure levels and lower temperatures. The uniaxial tensile tests were carried out at various temperatures and strain rates before the HPPF experiments. The flow stress of Ti-3Al-2.5V tubes is evidently affected by both temperature and strain rate. Because of this, the corner radii all change linearly over time at the pressurization stage but exponentially over time at the constant pressure stage. The cooling effect of the inflow process on the tubes results in temperature differences between the centre of the straight wall areas and the corner areas of the tubes during the inflow process. Adopting the lower pressurization rate and filling regenerative materials into the tube are effective methods for decreasing or eliminating the temperature difference.

show abstract

An Approach to Improve Thickness Uniformity of TA15 Tubular Part Formed by Gas Bulging Process

Cited by 13 publications

References 6 publications

High Pressure Pneumatic Forming of Ti-3Al-2.5V Titanium Tubes in a Square Cross-Sectional Die

High Pressure Pneumatic Forming of Ti-3Al-2.5V Titanium Tubes in a Square Cross-Sectional Die

Effect of feeding length on deforming behavior of Ti-3Al-2.5 V tubular components prepared by tube gas forming at elevated temperature

Effects of flow stress behaviour, pressure loading path and temperature variation on high-pressure pneumatic forming of Ti-3Al-2.5V tubes

Contact Info

Product

Resources

About