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

• Published in: Advanced engineering materials Vol. 21; no. 4
• Main Authors: Nawaya, Tarik, Hehl, Axel, Wagner, Sabine, Beck, Werner
• Format: Journal Article
• Language: English
• Published: 01.04.2019
• Subjects: Gleeble 3500; hot creep forming; hot sizing; stress relaxation; titanium exhaust systems
• ISSN: 1438-1656; 1527-2648
• DOI: 10.1002/adem.201800544

Hot deep drawing (HDD) is an innovative promising compromise to reduce costs by saving production time and to reduce the expenses for surface treatment. Parts made by HDD provide a high accuracy and constant wall thickness suitable for automated industrial assembly. In this paper, the behavior of one near‐α titanium alloy, used to manufacture the components of exhaust systems, are observed during HDD. It aims at improving the mechanical properties of the formed component by means of an integrated annealing to prevent, or at least minimize, the spring back behavior. For this purpose, the parameters of HDD followed by the so‐called creep relaxation period are optimized. They are: heating time, forming temperature, creep strain, strain rate, and relaxation time. Based on a statistical experimental design, the experimental procedure are conducted by utilizing a forming dilatometer. The results reveal a considerable impact of relaxation time on the material behavior. In addition, variation of the strain rate has also an effect on the considered outputs. Regarding the aforementioned challenges, a set of parameter is suggested, with which all the expected drawbacks can be diminished. Behavior of α‐Titanium under hot creep forming: Owing to its very high oxidation resistance as well as the convenient weldability, an α titanium alloy called (1.2KSANEX) is used to manufacture components for exhaust‐ and air bleed systems. Hot creep forming is suggested as a developed manufacturing method, by which Time and power are saved ensuring a precise part with no need of any post treatment.