Affiliation:
1. Centro Nacional de Investigaciones Metalúrgicas
2. Universidad de Castilla
3. CENIM-CSIC
Abstract
The improvement of optimization numerical methods for constitutive equations has been the first aim of this research. A subordinate optimization algorithm, based on Newton method, through “ad hoc” assessment, has been developed. Application to hot torsion data of AISI4145 with two grain sizes has been carried out. It is concluded that the Newton method is an excellent algorithm for the optimization of strain dependent constitutive equations. Two models are presented as alternative to the generalized Garofalo model: the normalized stress exponent model (NSE) and the Generalized Sherby model (SG). The NSE model is the most precise to restitute the experimental stress-strain curves.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
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