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Title: Anisotropic and Mechanical Behavior of 22MnB5 in Hot Stamping Operations

Abstract

The hot stamping of quenchable High Strength Steels offers the possibility of weight reduction in structural components maintaining the safety requirements together with enhanced accuracy and formability of sheets. The proper design of this technology requires a deep understanding of material behavior during the entire process chain, in terms of microstructural evolution and mechanical properties at elevated temperatures, in order to perform reliable FE simulations and obtain the desired characteristic on final parts. In particular, the analysis of technical-scientific literature shows that accurate data on material rheological behavior are difficult to find; while the lack of knowledge about anisotropic behavior at elevated temperatures is even more evident. To overcome these difficulties, a new experimental set-up was developed to reproduce the thermo-mechanical conditions of the industrial process and evaluate the influence of temperature and strain rate on 22MnB5 flow curves through uniaxial tensile tests; an optical strain measurement system was utilized to evaluate the effective strain after necking. From the same data, plastic anisotropy evolution was determined by means of a specially developed procedure. The influence of different cooling rates was taken into account and the rheological properties were correlated with microstructural changes occurring during deformation, previously evaluated through a dilatometricmore » analysis performed in the same range of temperatures.« less

Authors:
;  [1];  [2]
  1. DIMEG, University of Padova, Via Venezia 1, 35131, Padova (Italy)
  2. DIMS, University of Trento, Via Mesiano 77, 38050, Trento (Italy)
Publication Date:
OSTI Identifier:
21057013
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 907; Journal Issue: 1; Conference: 10. ESAFORM conference on material forming, Zaragoza (Spain), 18-20 Apr 2007; Other Information: DOI: 10.1063/1.2729514; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; COMPUTERIZED SIMULATION; COOLING; DEFORMATION; MECHANICAL PROPERTIES; MICROSTRUCTURE; PLASTICITY; SHEETS; STEELS; STRAIN RATE; STRAINS; TEMPERATURE DEPENDENCE; THERMOMECHANICAL TREATMENTS

Citation Formats

Turetta, A., Ghiotti, A., and Bruschi, S. Anisotropic and Mechanical Behavior of 22MnB5 in Hot Stamping Operations. United States: N. p., 2007. Web. doi:10.1063/1.2729514.
Turetta, A., Ghiotti, A., & Bruschi, S. Anisotropic and Mechanical Behavior of 22MnB5 in Hot Stamping Operations. United States. doi:10.1063/1.2729514.
Turetta, A., Ghiotti, A., and Bruschi, S. Sat . "Anisotropic and Mechanical Behavior of 22MnB5 in Hot Stamping Operations". United States. doi:10.1063/1.2729514.
@article{osti_21057013,
title = {Anisotropic and Mechanical Behavior of 22MnB5 in Hot Stamping Operations},
author = {Turetta, A. and Ghiotti, A. and Bruschi, S.},
abstractNote = {The hot stamping of quenchable High Strength Steels offers the possibility of weight reduction in structural components maintaining the safety requirements together with enhanced accuracy and formability of sheets. The proper design of this technology requires a deep understanding of material behavior during the entire process chain, in terms of microstructural evolution and mechanical properties at elevated temperatures, in order to perform reliable FE simulations and obtain the desired characteristic on final parts. In particular, the analysis of technical-scientific literature shows that accurate data on material rheological behavior are difficult to find; while the lack of knowledge about anisotropic behavior at elevated temperatures is even more evident. To overcome these difficulties, a new experimental set-up was developed to reproduce the thermo-mechanical conditions of the industrial process and evaluate the influence of temperature and strain rate on 22MnB5 flow curves through uniaxial tensile tests; an optical strain measurement system was utilized to evaluate the effective strain after necking. From the same data, plastic anisotropy evolution was determined by means of a specially developed procedure. The influence of different cooling rates was taken into account and the rheological properties were correlated with microstructural changes occurring during deformation, previously evaluated through a dilatometric analysis performed in the same range of temperatures.},
doi = {10.1063/1.2729514},
journal = {AIP Conference Proceedings},
number = 1,
volume = 907,
place = {United States},
year = {Sat Apr 07 00:00:00 EDT 2007},
month = {Sat Apr 07 00:00:00 EDT 2007}
}
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