Non-conventional Tensile Specimen for Mechanical Characterization of Tubular Materials

Abstract

AbstractInnovative tensile specimen was designed to probe the mechanical properties of the tube with a diameter/thickness ratio equal to 25 made of widely used aluminum alloy AA6063-T6. The proposed design is a specific tensile sample cut along the tube axial direction to determine the work hardening behavior and the anisotropy. We employed the electro discharge machine (EDM) wire cutting technique to minimize the effect of cutting force on the specimen. The developed tubular tensile test specimen is characterized with twin calibrated zones and it is mounted on a tensile testing machine using simple inserts. The designed tensile specimen was optimized using finite element method in order to meet the uniaxial tensile test state. The retained design was cut from the tube and experimental tests have been carried out. 3D Digital Image Correlation (DIC) using ARAMIS system is utilized to probe the current full field deformations. It has been observed from the experimental and numerical results that the gauge area of the proposed specimen experiences uniaxial stress and strain states. The proposed tensile sample is, therefore, a suitable design and an alternative to the standard sample, which presents some difficulties to be extracted from tubes, particularly from small diameter tubes.KeywordsTensile testTubeFlow stress curveDICAnisotropy