Dislocation substructure in fatigued duplex stainless steel

Journal Article · Wed Dec 15 04:00:00 EST 1993 · Scripta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-716X(93)90276-X· OSTI ID:5791759

Polak, J ^[1]; Degallaix, S ^[2]; Kruml, T ^[3]

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1. Ecole Centrale de Lille, Villeneuve d'Ascq (France). Lab. de Mecanique de Lille Inst. of Physical Metallurgy, Brno (Czechoslovakia). Academy of Sciences
2. Ecole Centrale de Lille, Villeneuve d'Ascq (France). Lab. de Mecanique de Lille
3. Inst. of Physical Metallurgy, Brno (Czechoslovakia). Academy of Sciences

Cyclic plastic straining of crystalline materials results in the formation of specific dislocation structures. Considerable progress in mapping and understanding internal dislocation structures has been achieved by studying single crystal behavior: however, most structural materials have a polycrystalline structure and investigations of polycrystals in comparison to single crystal behavior of simple metals prove to be very useful in understanding more complex materials. There are some classes of materials, however, with complicated structure which do not have a direct equivalent in single crystalline form. Moreover, the specific dimensions and shapes of individual crystallites play an important role both in the cyclic stress-strain response of these materials and in the formation of their interior structure in cyclic straining. Austenitic-ferritic duplex stainless steel, which is a kind of a natural composite, is a material of this type. The widespread interest in the application of duplex steels is caused by approximately doubled mechanical properties and equal corrosion properties, when compared with classical austenitic stainless steels. Fatigue resistance of these steels as well as the surface damage evolution in cyclic straining have been studied; however, much less is known about the internal substructure development in cyclic straining. In this study the dislocation arrangement in ferritic and austenitic grains of the austenitic-ferritic duplex steel alloyed with nitrogen and cyclically strained with two strain amplitudes, is reported and compared to the dislocation arrangement found in single and polycrystals of austenitic and ferritic materials of a similar composition and with the surface relief produced in cyclic plastic straining.

• OSTI ID: 5791759
• Journal Information: Scripta Metallurgica et Materialia; (United States), Journal Name: Scripta Metallurgica et Materialia; (United States) Vol. 29:12; ISSN SCRMEX; ISSN 0956-716X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360103 -- Metals & Alloys-- Mechanical Properties
ALLOYS
AUSTENITIC STEELS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISLOCATIONS
FATIGUE
FERRITIC STEELS
HIGH ALLOY STEELS
IRON ALLOYS
IRON BASE ALLOYS
LINE DEFECTS
MECHANICAL PROPERTIES
MICROSTRUCTURE
STAINLESS STEELS
STEELS