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Construction of Modified Yield Loci with Respect to the Strain Rates using Hill48 Quadratic Yield Function  

Lee, Chang-Soo (School of Mechanical, Aerospace & Systems Engineering, KAIST)
Bae, Gi-Hyun (School of Mechanical, Aerospace & Systems Engineering, KAIST)
Kim, Seok-Bong (School of Mechanical, Aerospace & Systems Engineering, KAIST)
Huh, Hoon (School of Mechanical, Aerospace & Systems Engineering, KAIST)
Publication Information
Transactions of the Korean Society of Automotive Engineers / v.18, no.2, 2010 , pp. 56-60 More about this Journal
Abstract
Since the forming process involves the strain rate effect, a yield function considering the strain rate is indispensible to predict the accurate final blank shape in the forming simulation. One of the most widely used in the forming analysis is the Hill48 quadratic yield function due to its simplicity and low computing cost. In this paper, static and dynamic uni-axial tensile tests according to the loading direction have been carried out in order to measure the yield stress and the r-value. Based on the measured results, the Hill48 yield loci have been constructed, and their performance to describe the plastic anisotropy has been quantitatively evaluated. The Hill48 quadratic yield function has been modified using convex combination in order to achieve accurate approximation of anisotropy at the rolling and transverse direction.
Keywords
Hill48 quadratic yield function; Strain rate; Convex combination; Plastic anisotropy; r-value;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
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