Investigation of hot deformation characteristics of AISI 4340 steel using processing map

Conference proceedings article

Authors/Editors

Strategic Research Themes

No matching items found.

Publication Details

Author list: Sanrutsadakorn A., Uthaisangsuk V., Suranuntchai S., Thossatheppitak B.

Publisher: Trans Tech Publications

Publication year: 2013

Volume number: 683

Start page: 301

End page: 306

Number of pages: 6

ISBN: 9783037856666

ISSN: 1022-6680

eISSN: 1662-8985

URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84878290450&doi=10.4028%2fwww.scientific.net%2fAMR.683.301&partnerID=40&md5=ecc86ac562ea58207e7620c23a2a5a9a

Languages: English-Great Britain (EN-GB)

View in Web of Science | View on publisher site | View citing articles in Web of Science

Abstract

Uniaxial compression tests at various temperatures from 850 ฐC to 1200 ฐC and strain rates between 0.01 s-1 and 10 s-1 were carried out in order to determine hot working characteristic of the AISI 4340 steel. The plastic stress-strain responses at high temperatures of the steel were provided. Constitutive relationship between the flow stresses and the Zener-Hollomon parameters was primarily established by means of a hyperbolic sine function for the entire range of the investigated conditions. Afterwards, the power dissipation map and instability map were developed on the basis of the Dynamic Materials Model (DMM). The variation of efficiency of the power dissipation calculated as a function of strain rate sensitivity represented material behaviors according to the microstructure evolution. The peak efficiency indicated an optimum processing window for hot working. In this study, processing map was obtained by a superimposition of the power dissipation and the instability criterion. The domains of temperature and strain rate, in which material flow stability occurred, were determined. For the AISI 4340 steel, the processing maps exhibited a distinct domain with its peak efficiency at about 1050-1200 ฐC and 0.01-0.1 s-1, in which the peak efficiencies of about 40-50% were shown for different strains. In combination with microstructure observations after hot deformation, dynamic recrystallization zone could be identified in the processing map at a certain strain. ฉ (2013) Trans Tech Publications, Switzerland.

Keywords

AISI 4340, Dynamic recrystallization, Hot deformation, Processing maps