Micro Sheet Hydroforming Process of Ultra-Thin Pure Titanium Foil

Abstract

A micro hydromechanical deep drawing is carried out using the pure titanium and the effect of fluid pressure on formability of pure titanium is investigated. The experiments are performed using the two kinds of pure titanium foils (TR270C-H and TR270C-O) and stainless steel foil (SUS304-H) with 50 thickness and the cylindrical and conical punches. As a result, it is found that the peeling off the oxide film of pure titanium can be reduced by applying the fluid pressure because the friction force and contact pressure between the blank and die decreases. However, the formability is lower for pure titanium than that for stainless steel because the tensile strength is low and the friction force is easy to increase as the friction force increases. In contrast, due to the low young modulus of pure titanium, the restriction of wrinkling, decrease of friction force and friction holding effect can be obtained at low fluid pressure.

A study of influence of hydraulic pressure on micro-hydromechanical deep drawing considering size effects and surface roughness

“…Forming limit and dimensional accuracy were improved in MHDD experiments with different metal foils [21]. Hydraulic pressure helps to reduce oxide film peeling from the foil [29], and affects wrinkling and earing of drawn cups [30].…”

Effects of Hydraulic Pressure on Shape Accuracy of Drawn Circular Cups during Micro Hydro Deep Drawing

“…Micro hydro deep drawing has drawn increasing attention due to an attempt to utilise the benefits of the hydraulic pressure to produce micro metal products with complex 3D shapes [4]. Nevertheless, the micro hydro deep drawing process is relatively fast and fluid chamber is relatively large, which lead to difficulties in accurate pressure control.…”

Effects of hydraulic pressure on wrinkling and earing in micro hydro deep drawing of SUS304 circular cups

“…With an attempt to improve the quality of micro deep drawn cups, micro hydro deep drawing (MHDD) has been introduced [8][9][10][11]. However, the size effects change the impacts of the hydraulic pressure in the micro hydro deep drawing [12].…”