Effect of Warm Temperature on Springback Compensation of Titanium Sheet

Abstract

In the present study, the effect of warm temperature on springback compensation of commercially pure grade 2 (CP2) titanium sheet is investigated. The results reveal that the springback is substantially reduced with increasing temperature. The elastic energy and the ratio of tensile strength/yield strength (TS/YS) of the material are measured at various temperatures under tensile loading condition. A gradual decrease of elastic energy is observed with increasing temperature. The change in the ratio of TS/YS is left diminutive with increasing temperature. IntroductionTitanium (Ti) and its alloys are widely used in aerospace applications due to their high strength-to-weight ratio, excellent mechanical properties,corrosion, and thermal resistance. They are 45% lighter than steel and 60% heavier than aluminum. They have very attractive features such as higher melting points, and corrosion and thermal resistance, which are the best of all known metallic materials. That is why titanium and its alloys are widely used in various applications [1,2]. Titanium is known as a rare element in the earth's crust, despite the fact it is the ninth most abundant element and is the seventh metal used [3]. Titanium and its alloys have been widely used in various applications such as aircraft components, biomedical implant applications, hand tools, and sport equipments. Titanium can be found in various forms such as sheets, strips, plates, foil, rounds, tubes, pipes, and wire. Because of sheet and plate forms are strain hardened by cold forming of the material, the tensile strength (TS) and yield strength (YS) increase, while ductility decreases. Formability of titanium is very important in its various application areas. Although pure titanium has a good formability, its springback after the forming is severe due to its high yield strength and low modulus of elasticity. There is a serious problem with springback; therefore, the great majority of formed titanium components are made by hot forming or cold forming followed by hot sizing to overcome this problem. Springback is defined as an elastic behavior of material which tries to return its original shape after removing the forming forces on the formed parts. It creates serious problems during the assembling of the parts. The amount of the springback can be associated with material properties, forming conditions, and tool

Hot Deep Drawing Processing of Titanium Sheet Metal Parts for High Temperature Applications

“…The authors in ref. assumes that forming in elevated temperature benefits avoiding the spring back effect of commercial titanium grade 02. The regarded alloy in our study reveals also such consistent results, so that a complete stress relief could have been reached with a forming temperature starting from 720 °C.…”

“…Compared to superplastic forming, the process temperatures of hot deep drawing are considerably lower, which makes hot deep drawing to a forming technology, that is, potentially more suitable to produce titanium applications such as exhaust systems. On the other hand, decrease the forming temperature raises the spring back effect owing to the fact that the titanium alloys in general possesses a high elastic energy . In refs.…”

“…In refs. , the authors studied the optimization process of Ti6Al4V alloy sheets as the most used titanium alloy in the industry, and suggested an additional process stage adapted to the forming process, namely the hot sizing. In this subsequent stage, the sheet is kept loaded for a period, after being hot deep drawn, the reached strain will be held, inducing a stress relief in the microstructure.…”

A cost-effective method for rapid manufacturing sheet metal forming dies

“…The most commonly employed approach of rapid tooling is a fabrication of silicone rubber mold using rapid prototyping master model [13]. The proposed approach incorporates pattern-based methods where the silicone rubber molds were Figure 4 shows the results of a prototype of punch and die, silicone rubber molds of punch and die, and punch and die fabricated from epoxy resins.…”

Experimental and Numerical Method for the Analysis of Warm Titanium Sheet Stamping of an Automotive Component

“…Therefore, Ti sheet applications can be limited especially when high deformations or complex parts are considered [6]. In order to overcome these limitations, [7] proposed a multistage forming process while [8] studied the effect of temperature in reducing the tensile/yield strengths ratio of the material so to reduce the elastic recovery of the part.…”