Elevated temperature material properties of stainless steel alloys

Appropriate assessment of the fire resistance of structures depends largely on the ability to accurately predict the material response at elevated temperature. The material characteristics of stainless steel differ from those of carbon steel due to the high alloy content. These differences have been explored in some detail at room temperature, whilst those at elevated temperature have been less closely scrutinised. This paper presents an overview and reappraisal of previous pertinent research, together with an evaluation of existing elevated temperature stainless steel stress-strain test data and previously proposed material models. On the basis of examination of all available test data, much of which have been recently generated, revised strength and stiffness reduction factors at elevated temperatures for a range of grades of stainless steel have been proposed, including four grades not previously covered by existing structural fire design guidance. A total of eight sets of strength reduction factors are currently provided for different grades of stainless steel in EN 1993-1-2 and the Euro Inox/SCl Design Manual for Structural Stainless Steel, compared to a single set for carbon steel. A number of sets of reduction factors is appropriate for stainless steel since the elevated temperature properties can vary markedly between different grades, but this has to be justified with sufficient test data and balanced against ease of design - it has been proposed herein that the eight sets of reduction factors be rationalised on the basis of grouping grades that exhibit similar elevated temperature properties. In addition to more accurate prediction of discrete features of the elevated temperature material stress-strain response of stainless steel (i.e. strength and stiffness reduction factors), a material model for the continuous prediction of the stress-strain response by means of a modified compound Ramberg-Osgood formulation has also been proposed. The proposed model is less complex than the current provisions of EN 1993-1-2, more accurate when compared to test results, and the model parameters have a clear physical significance. © 2010 Elsevier Ltd. All rights reserved.

[1]  B. R. Kirby,et al.  High temperature properties of hot-rolled, structural steels for use in fire engineering design studies , 1988 .

[2]  Gordon M. E. Cooke,et al.  An introduction to the mechanical properties of structural steel at elevated temperatures , 1988 .

[3]  Kenzu Abdella,et al.  An explicit stress formulation for stainless steel applicable in tension and compression , 2007 .

[4]  E. Mirambell,et al.  On the calculation of deflections in structural stainless steel beams: an experimental and numerical investigation , 2000 .

[5]  Y. Sakumoto,et al.  High-Temperature Properties of Stainless Steel for Building Structures , 1996 .

[6]  H. N. Hill Determination of stress-strain relations from "offset" yield strength values , 1944 .

[7]  Leroy Gardner,et al.  Strength enhancements induced during cold forming of stainless steel sections , 2008 .

[8]  Chanakya Arya,et al.  Eurocode 3: Design of steel structures , 2018, Design of Structural Elements.

[9]  Tiina Ala-Outinen,et al.  Fire resistance of austenitic stainless steels Polarit 725 (EN 1.4301) and Polarit 761 (EN 1.4571) , 1996 .

[10]  Ben Young,et al.  Stress–strain curves for stainless steel at elevated temperatures , 2006 .

[11]  Ulf Wickström,et al.  Comments on calculation of temperature in fire-exposed bare steel structures in prEN 1993-1-2: Eurocode 3—design of steel structures—Part 1–2: general rules—structural fire design , 2005 .

[12]  Leroy Gardner,et al.  Fire testing and design of stainless steel structures , 2006 .

[13]  C. Davies Predicting creep crack initiation in austenitic and ferritic steels using the creep toughness parameter and time‐dependent failure assessment diagram , 2009 .

[14]  Yong Wang,et al.  Steel and Composite Structures: Behaviour and Design for Fire Safety , 2002 .

[15]  David A. Nethercot,et al.  Finite element modelling of structural stainless steel cross-sections , 2006 .

[16]  Andrew H. Buchanan,et al.  Structural Design for Fire Safety , 2001 .

[17]  Leroy Gardner Stainless steel structures in fire , 2007 .

[18]  Kim Rasmussen,et al.  Full-range stress–strain curves for stainless steelalloys , 2003 .

[19]  Milan Veljkovic,et al.  A design model for stainless steel box columns in fire , 2008 .

[20]  Leroy Gardner,et al.  Structural design of high-strength austenitic stainless steel , 2006 .

[21]  Jean-Marc Franssen,et al.  Lateral-torsional buckling of stainless steel I-beams in case of fire , 2008 .

[22]  David A. Nethercot,et al.  Experiments on stainless steel hollow sections—Part 1: Material and cross-sectional behaviour , 2004 .

[23]  W. Ramberg,et al.  Description of Stress-Strain Curves by Three Parameters , 1943 .

[24]  Leroy Gardner,et al.  Testing and numerical modelling of lean duplex stainless steel hollow section columns , 2009 .

[25]  Raymond Ogden,et al.  Architects' guide to stainless steel , 1997 .

[26]  Mahmud Ashraf,et al.  Structural design for non-linear metallic materials , 2006 .

[27]  Leroy Gardner,et al.  The use of stainless steel in structures , 2005 .

[28]  David A. Nethercot,et al.  Structural stainless steel design: Resistance based on deformation capacity , 2008 .

[29]  Leroy Gardner,et al.  Development of the use of stainless steel in construction , 2001 .

[30]  Tiina Ala-Outinen,et al.  Stainless steel compression members exposed to fire , 1997 .

[31]  Leroy Gardner,et al.  Temperature development in structural stainless steel sections exposed to fire , 2006 .