Abstract
The effect of thickness on the mechanical properties of Al 6K21-T4 sheet specimens under uniaxial tension was investigated. In order to reduce the thickness of the specimens without changing the microstructure and grain size, chemical etching was carried out, resulting in Al sheets ranging from 0.40 mm to 1.58 mm in thickness. Additionally, the effect of surface roughness was determined by finite element (FE) calculations performed using FE code MARC 2007. Tensile specimens of varying surface roughness were modeled and simulated. An analysis of the combined effects of the thickness and surface roughness revealed that the yield and tensile strengths decreased when the number of grains over the thickness was decreased. The ductility also decreased when reducing the thickness. An FE simulation showed that both the surface roughness and thickness affected the flow-curve shape. Moreover, the effect of the surface roughness tended to increase when decreasing the sheet thickness of specimens having the same roughness.
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This paper was recommended for publication in revised form by Associate Editor Seong Beom Lee
Young Suk Kim is currently a professor, Department of Mechanical Engineering, Kyungpook National University in Daegu, Korea. He received his B.S. degree from Hanyang University in 1979 and M.S. degree from Seoul National University in 1981. He received his Ph.D degree from Kobe University, Japan, in 1986. Dr. Kim’s research interests include sustainable material processing, nano/micro mechanics, FEM and biomechanics.
Chang Hee Suh is currently a senior researcher at the Daegu Machinery Institute of Components & Materials. He received his B.S. and M.S. degrees in Mechanical Engineering from Kyungpook National University, Korea, in 1998 and 2001. His research interests include computational mechanics, material processing, and fracture mechanics.
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Suh, C.H., Jung, YC. & Kim, Y.S. Effects of thickness and surface roughness on mechanical properties of aluminum sheets. J Mech Sci Technol 24, 2091–2098 (2010). https://doi.org/10.1007/s12206-010-0707-7
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DOI: https://doi.org/10.1007/s12206-010-0707-7