YIELD STRENGTH OF NITROGEN ALLOYED DUPLEX STEELS: HALL-PETCH ANALYSIS AND MICROMECHANICAL PREDICTIONS

E. A. Werner, W. Horvath, W. Prantl

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

For the prediction of the yield strength of nitrogen alloyed ferritic-austenitic duplex steels, accurate knowledge on the single phases' yield strength and their geometrical arrangement within the duplex microstructure is required. Since the matrix-inclusion character of the phases markedly influences the yield strength σdyof duplex steels, linear models for σdy(Voigt-model) cannot serve for an accurate prediction of af. A non-linear rule of mixture, however, is a more sophisticated approach to calculate σdy. Micromechanical models combined with finite element computations are efficient tools to accurately predict the influence of the topology of the microstructure on σdyonly if the yield strengths of the single phases are distinctly different, i.e. the yield strength ratio of ferrite to austenite xp is larger than 2. Experiments on duplex steels show, however, a marked influence of the phase arrangement on σdyeven for ψ ∼ 1. To explain this behavior a modified non-linear rule of mixture is proposed, which incorporates the in-situ yield strengths of the phases as upper and lower bounds for σdy. The discrepancy between the experiments (and their analysis) and the predictions from the micromechanical approach convincingly demonstrates the necessity to include crystallographic details such as dislocation - interface boundary interactions and misorientation and crystal structures of adjacent grains in improved micromechanical models for the yield strength of duplex steel microstructures.

Original languageEnglish
Title of host publicationRecent Advances in Solids/Structures and Application of Metallic Materials
PublisherAmerican Society of Mechanical Engineers (ASME)
Pages273-282
Number of pages10
ISBN (Electronic)9780791818282
DOIs
StatePublished - 1997
Externally publishedYes
EventASME 1997 International Mechanical Engineering Congress and Exposition, IMECE 1997 - Recent Advances in Solids/Structures and Application of Metallic Materials - Dallas, United States
Duration: 16 Nov 199721 Nov 1997

Publication series

NameASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE)
Volume1997-AC

Conference

ConferenceASME 1997 International Mechanical Engineering Congress and Exposition, IMECE 1997 - Recent Advances in Solids/Structures and Application of Metallic Materials
Country/TerritoryUnited States
CityDallas
Period16/11/9721/11/97

Fingerprint

Dive into the research topics of 'YIELD STRENGTH OF NITROGEN ALLOYED DUPLEX STEELS: HALL-PETCH ANALYSIS AND MICROMECHANICAL PREDICTIONS'. Together they form a unique fingerprint.

Cite this