Investigation of stress-strain behavior of a sheet material using free bulging test

• DOI: 10.1016/j.proeng.2017.10.957
• Publication Date: 2017-11-15T17:15:45Z
• Authors: Sergey A. Aksenov; Donato Sorgente
• Keywords: Superplasticity; Tensile testing; Dome (geology); Tension (geology)

In this work, a new experimental-numerical technique is developed in order to investigate the constitutive behaviour of sheet material conditions superplastic forming. The principal feature that unlike classical tensile testing it allows one obtain stress-strain curves for formed biaxial tension produced by free bulging process. These are much closer ones undergoes during forming Consequently, they give more accurate information about than coming from tests data. drawback strain (and similarly its time derivative) cannot be directly measured and controlled test but value has derived other macroscopic measurement. Towards end, blow machine was equipped with position transducer measurement dome height test. control stress apex at predetermined level applied pressure continuously adjusted current using special algorithm. After test, data were processed evolution stress, rate as well constant referenced rates. performed on aluminium alloy (ALNOVI-U) sheets 1.35 mm initial thickness 500 °C. Using two different paths sensitivity index calculated obtained verified finite element simulation