• Nguyen Thi Thu Hanoi University of Science and Technology
  • Nguyen Hoang Duong Hanoi University of Science and Technology
  • Pham Quang Minh Military Institute of Science and Technology
Keywords: Free bulging stage, Liquid pressure, Hydrostatic forming, The depth of product, The maximum thinning


Hydrostatic forming is one of the most advanced technologies for forming tubular and sheet products. This technology has been highly applied in thin-shell manufacturing industries, especially in the automotive industry. However, the depth of the parts formed by this technology is limited by the early stage-the free bulging stage due to intense thinning of the metal. Therefore, it is necessary to control the thinning in this stage to ensure that the material can continue to deform in later stages. The types of materials used in this technology are also common materials as in conventional forming including ferrous and non-ferrous metals. Among them, copper materials with ductile properties are considered as one of the most popular. Copper behavior in the forming technology is still a new issue that needs to be explored. Therefore, in this paper, the free bulging process is studied during hydrostatic forming process for copper sheet using numerical simulation. The results show the influence of forming liquid pressure on the forming ability of copper materials, including forming depth and thinning in the free bulging phase.


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How to Cite
Nguyen Thi Thu, Nguyen Hoang Duong, & Pham Quang Minh. (2022). RESEARCH ON THE FREE BULGING STAGE IN HYDROSTATIC FORMING PROCESS FOR COPPER SHEET. UTEHY Journal of Science and Technology, 33, 87-92. Retrieved from