skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Microstructure and tensile behavior of nitrogen-alloyed, dual-phase stainless steels

Abstract

Two alloys of high-nitrogen stainless steel have been heat treated to produce dual-phase microstructures. The first alloy, N10CrNiMo17 1, a Ni-containing stainless steel, was processed conventionally. The second alloy, N20CrMo17, a Ni-free stainless steel, was processed to obtain a higher nitrogen content by pressurized electroslag remelting. The martensite in N10CrNiMo17 1 was homogeneously distributed in the ferrite and obtained a near-constant volume fraction as a function of intercritical annealing temperature. Microprobe analysis and microhardness measurements of the martensite constituent suggested that up to 0.4 pct N was dissolved in the austenite before quenching. Austenite formation, martensite transformation, undissolved nitrides, and retained austenite were evaluated by transmission electron microscopy (TEM). The Ni-containing alloy exhibited classic dual-phase tensile behavior in that continuous yielding was observed together with good combinations of ultimate tensile strength and total elongation. The martensite constituent in alloy N20CrMo17 was concentrated within bands. Comparison of tensile properties of the two alloys at similar volume fractions and hardness levels of martensite and ferrite showed that the microstructure containing banded martensite had inferior combinations of strength and ductility. The degradation of tensile ductility was accompanied by a fracture mode transition from microvoid coalescence to transgranular cleavage. The deformation and fracture behaviormore » of both alloys were related to the microstructure.« less

Authors:
 [1];  [2];  [3];  [4]
  1. Ruhr Univ. Bochum (Germany). Lehrstuhl Werkstofftechnik
  2. ZF Friedrichshafen AG (Germany)
  3. Colorado School of Mines, Golden, CO (United States). Dept. of Metallurgical and Materials Engineering
  4. Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Metallurgical and Materials Engineering
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
282234
Resource Type:
Journal Article
Journal Name:
Metallurgical Transactions, A
Additional Journal Information:
Journal Volume: 27; Journal Issue: 7; Other Information: PBD: Jul 1996
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CHROMIUM-NICKEL-MOLYBDENUM STEELS; MICROSTRUCTURE; TENSILE PROPERTIES; FRACTURE PROPERTIES; CHROMIUM-MOLYBDENUM STEELS; NITROGEN; METALLURGICAL EFFECTS; HEAT TREATMENTS; FERRITE; AUSTENITE; MARTENSITE; ELECTRON MICROPROBE ANALYSIS; MICROHARDNESS; TRANSMISSION ELECTRON MICROSCOPY; ULTIMATE STRENGTH; ELONGATION; DUCTILITY

Citation Formats

Berns, H., Kleff, J., Krauss, G., and Foley, R.P. Microstructure and tensile behavior of nitrogen-alloyed, dual-phase stainless steels. United States: N. p., 1996. Web. doi:10.1007/BF02651934.
Berns, H., Kleff, J., Krauss, G., & Foley, R.P. Microstructure and tensile behavior of nitrogen-alloyed, dual-phase stainless steels. United States. doi:10.1007/BF02651934.
Berns, H., Kleff, J., Krauss, G., and Foley, R.P. Mon . "Microstructure and tensile behavior of nitrogen-alloyed, dual-phase stainless steels". United States. doi:10.1007/BF02651934.
@article{osti_282234,
title = {Microstructure and tensile behavior of nitrogen-alloyed, dual-phase stainless steels},
author = {Berns, H. and Kleff, J. and Krauss, G. and Foley, R.P.},
abstractNote = {Two alloys of high-nitrogen stainless steel have been heat treated to produce dual-phase microstructures. The first alloy, N10CrNiMo17 1, a Ni-containing stainless steel, was processed conventionally. The second alloy, N20CrMo17, a Ni-free stainless steel, was processed to obtain a higher nitrogen content by pressurized electroslag remelting. The martensite in N10CrNiMo17 1 was homogeneously distributed in the ferrite and obtained a near-constant volume fraction as a function of intercritical annealing temperature. Microprobe analysis and microhardness measurements of the martensite constituent suggested that up to 0.4 pct N was dissolved in the austenite before quenching. Austenite formation, martensite transformation, undissolved nitrides, and retained austenite were evaluated by transmission electron microscopy (TEM). The Ni-containing alloy exhibited classic dual-phase tensile behavior in that continuous yielding was observed together with good combinations of ultimate tensile strength and total elongation. The martensite constituent in alloy N20CrMo17 was concentrated within bands. Comparison of tensile properties of the two alloys at similar volume fractions and hardness levels of martensite and ferrite showed that the microstructure containing banded martensite had inferior combinations of strength and ductility. The degradation of tensile ductility was accompanied by a fracture mode transition from microvoid coalescence to transgranular cleavage. The deformation and fracture behavior of both alloys were related to the microstructure.},
doi = {10.1007/BF02651934},
journal = {Metallurgical Transactions, A},
number = 7,
volume = 27,
place = {United States},
year = {1996},
month = {7}
}