Investigation of the plastic anisotropy developed under necking in duplex stainless steels

• Grant number: 16/05768-2
• Support Opportunities: Regular Research Grants
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Claudio Geraldo Schon
• Grantee: Claudio Geraldo Schon
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Duplex stainless steels are mainly applied in situations where stress corrosion cracking and pitting corrosion resistance are required. These steels, however, are produced by forming, and, in particular, by rolling. It is known that the processing window for these steels is thigh, which impairs fabrication. On the other hand, these steels present a very interesting phenomenon, which is worth investigating. A sample submitted to tensile testing, which presents a regular initial geometry (either circular orsquare transverse sections) develops an anisotropic necking zone after fracture (with the transverse section becoming, respectively, elliptical and rectangular). The phenomenon is most surprising since the region of the specimen which remains homogeneously strained (that is, outside the necking zone) remains regular. This result suggest that this anisotropy develops due to the cavitation damage in the necking zone. Preliminary results by the present group confirms that the lamellar microstructure, typical of these steels, is responsible for the observed anisotropy. The present project aims at characterizing the phenomenon using interrupted tensile tests, which will allow to investigate the particularities of the codeformation of the austenite and ferrite phases, giving information to understand what limits forming in these materials. (AU)

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TERRICABRAS, ADRIA GALLIFA; SCHOEN, CLAUDIO GERALDO. Characterization of the anisotropic necking in duplex stainless steels with lamellar microstructures. MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, v. 717, p. 20-25, FEB 21 2018. (16/05768-2)

BRANDI, SERGIO DUARTE; SCHON, CLAUDIO GERALDO. A Thermodynamic Study of a Constitutional Diagram for Duplex Stainless Steels. JOURNAL OF PHASE EQUILIBRIA AND DIFFUSION, v. 38, n. 3, p. 268-275, JUN 2017. (16/05768-2)

DA SILVA, F. C.; TUNES, M. A.; EDMONDSON, P. D.; LIMA, N. B.; SAGAS, J. C.; FONTANA, L. C.; SCHOEN, C. G.. Grid-assisted magnetron sputtering deposition of nitrogen graded TiN thin films. SN APPLIED SCIENCES, v. 2, n. 5, MAY 2020. (16/05768-2)

SILVA, FELIPE C.; TUNES, MATHEUS A.; SAGAS, JULIO C.; FONTANA, LUIS C.; DE LIMA, NELSON B.; SCHON, CLAUDIO G.. Mechanical properties of homogeneous and nitrogen graded TiN thin films. Thin Solid Films, v. 710, p. 10-pg., 2020-09-30. (16/05768-2)