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

Title: Austenite stability and its influence on mechanical properties of 18-8 stainless steel at cryogenic temperatures. [SS 304LN]

Abstract

Stress/strain induced martensitic transformation has been found to play an important role on the mechanical properties of metastable austenitic stainless steels. Typical two-stage stress-strain curves were observed for AISI 304L and 304LN stainless steels containing 18% Cr and 8%Ni. The martensite phase induced in the high-work-hardening stage was found, by transmission electron microscopy, to be accommodated by mechanical twinning. The drop of 0.2% offset yield strength caused by the dilation and induced slip associated with the martensitic transformation of the low-carbon-content 304L was observed at liquid nitrogen temperature. Low temperature favorable fatigue properties were observed for 304L but not for 304LN. Below the M/sub d/ temperature, the fatigue crack propagation in metastable austenitic steels can be assumed to be the same as crack growth in an austenite and martensite composite. Although fatigue cracks grew faster in the martensite phase than in the austenite phase, the compressive stress near the crack tip due to the martensitic transformation appeared to reduce the effective stress intensity range which resulted in a decreased crack growth rate. The controlling factor became K/sub max/ instead of ..delta.. K if the load ratio R was not large. The addition of interstitial nitrogen, which stabilizes the austenite phase,more » reduced the compressive stress at crack tips and resulted in the temperature-insensitive fatigue properties. Both the austenite phase and the martensite phase were found to be ductile at liquid nitrogen temperature.« less

Authors:
Publication Date:
Research Org.:
Lawrence Berkeley Lab., CA (USA)
OSTI Identifier:
5837219
Report Number(s):
LBL-15864
ON: DE83016682
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Technical Report
Resource Relation:
Other Information: Thesis
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; STAINLESS STEEL-18-8; MECHANICAL PROPERTIES; STAINLESS STEEL-304L; AUSTENITE; CRACK PROPAGATION; FATIGUE; LOW TEMPERATURE; MARTENSITE; YIELD STRENGTH; ALLOYS; CARBON ADDITIONS; CHROMIUM ALLOYS; CHROMIUM STEELS; CHROMIUM-NICKEL STEELS; CORROSION RESISTANT ALLOYS; HEAT RESISTANT MATERIALS; HEAT RESISTING ALLOYS; IRON ALLOYS; IRON BASE ALLOYS; MATERIALS; NICKEL ALLOYS; STAINLESS STEELS; STEELS; 360103* - Metals & Alloys- Mechanical Properties

Citation Formats

Chang, G M. Austenite stability and its influence on mechanical properties of 18-8 stainless steel at cryogenic temperatures. [SS 304LN]. United States: N. p., 1983. Web.
Chang, G M. Austenite stability and its influence on mechanical properties of 18-8 stainless steel at cryogenic temperatures. [SS 304LN]. United States.
Chang, G M. 1983. "Austenite stability and its influence on mechanical properties of 18-8 stainless steel at cryogenic temperatures. [SS 304LN]". United States.
@article{osti_5837219,
title = {Austenite stability and its influence on mechanical properties of 18-8 stainless steel at cryogenic temperatures. [SS 304LN]},
author = {Chang, G M},
abstractNote = {Stress/strain induced martensitic transformation has been found to play an important role on the mechanical properties of metastable austenitic stainless steels. Typical two-stage stress-strain curves were observed for AISI 304L and 304LN stainless steels containing 18% Cr and 8%Ni. The martensite phase induced in the high-work-hardening stage was found, by transmission electron microscopy, to be accommodated by mechanical twinning. The drop of 0.2% offset yield strength caused by the dilation and induced slip associated with the martensitic transformation of the low-carbon-content 304L was observed at liquid nitrogen temperature. Low temperature favorable fatigue properties were observed for 304L but not for 304LN. Below the M/sub d/ temperature, the fatigue crack propagation in metastable austenitic steels can be assumed to be the same as crack growth in an austenite and martensite composite. Although fatigue cracks grew faster in the martensite phase than in the austenite phase, the compressive stress near the crack tip due to the martensitic transformation appeared to reduce the effective stress intensity range which resulted in a decreased crack growth rate. The controlling factor became K/sub max/ instead of ..delta.. K if the load ratio R was not large. The addition of interstitial nitrogen, which stabilizes the austenite phase, reduced the compressive stress at crack tips and resulted in the temperature-insensitive fatigue properties. Both the austenite phase and the martensite phase were found to be ductile at liquid nitrogen temperature.},
doi = {},
url = {https://www.osti.gov/biblio/5837219}, journal = {},
number = ,
volume = ,
place = {United States},
year = {1983},
month = {6}
}

Technical Report:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that may hold this item. Keep in mind that many technical reports are not cataloged in WorldCat.

Save / Share: