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International Journal of Applied Mechanics and Engineering

The Journal of University of Zielona Góra

Editor-in-Chief: Walicki, Edward

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Determination of Constant Parameters of Copper as Power-Law Hardening Material at Different Test Conditions

Md. A. Kowser
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  • Department of Mechanical Engineering Dhaka University of Engineering and Technology (DUET) Gazipur, Bangladesh
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/ Md. Mahiuddin
  • Department of Mechanical Engineering Dhaka University of Engineering and Technology (DUET) Gazipur, Bangladesh
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Published Online: 2014-12-30 | DOI: https://doi.org/10.2478/ijame-2014-0047


In this paper a technique has been developed to determine constant parameters of copper as a power-law hardening material by tensile test approach. A work-hardening process is used to describe the increase of the stress level necessary to continue plastic deformation. A computer program is used to show the variation of the stress-strain relation for different values of stress hardening exponent, n and power-law hardening constant, α . Due to its close tolerances, excellent corrosion resistance and high material strength, in this analysis copper (Cu) has been selected as the material. As a power-law hardening material, Cu has been used to compute stress hardening exponent, n and power-law hardening constant, α from tensile test experiment without heat treatment and after heat treatment. A wealth of information about mechanical behavior of a material can be determined by conducting a simple tensile test in which a cylindrical specimen of a uniform cross-section is pulled until it ruptures or fractures into separate pieces. The original cross sectional area and gauge length are measured prior to conducting the test and the applied load and gauge deformation are continuously measured throughout the test. Based on the initial geometry of the sample, the engineering stress-strain behavior (stress-strain curve) can be easily generated from which numerous mechanical properties, such as the yield strength and elastic modulus, can be determined. A universal testing machine is utilized to apply the load in a continuously increasing (ramp) manner according to ASTM specifications. Finally, theoretical results are compared with these obtained from experiments where the nature of curves is found similar to each other. It is observed that there is a significant change of the value of n obtained with and without heat treatment it means the value of n should be determined for the heat treated condition of copper material for their applications in engineering fields.

Keywords : stress hardening exponent; power-law hardening constant; work-hardening process; power-law hardening material; heat treatment; tensile test; stress-strain curve


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About the article

Received: 2013-10-18

Revised: 2014-10-10

Published Online: 2014-12-30

Published in Print: 2014-11-01

Citation Information: International Journal of Applied Mechanics and Engineering, Volume 19, Issue 4, Pages 687–698, ISSN (Online) 1734-4492, DOI: https://doi.org/10.2478/ijame-2014-0047.

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© 2015. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. BY-NC-ND 3.0

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