Tensile Deformation Behavior of Duplex Stainless Steel Studied by In-Situ Time-of-Flight Neutron Diffraction

• Published in: Metallurgical and materials transactions. A, Physical metallurgy and materials science Physical metallurgy and materials science, 2008-12, Vol.39 (13), p.3134-3140
• Main Authors: Jia, N., Lin Peng, R., Brown, D.W., Clausen, B., Wang, Y.D.
• Format: Article
• Language: English
• Subjects: Applied sciences; Characterization and Evaluation of Materials; Chemistry and Materials Science; Exact sciences and technology; Materials research; Materials Science; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metallic Materials; Metals. Metallurgy; Nanotechnology; Plastic deformation; Residual stress; Stainless steel; Strain hardening; Stress corrosion cracking; Structural Materials; Surfaces and Interfaces; Symposium: Neutron and X-Ray Studies for Probing Materials Behavior; TECHNOLOGY; TEKNIKVETENSKAP; Thin Films
• ISSN: 1073-5623; 1543-1940
• DOI: 10.1007/s11661-008-9675-2

For a duplex alloy being subjected to deformation, the different mechanical behaviors of its constituent phases may lead to a nonuniform partition of stresses between phases. In addition, the grain-orientation-dependent elastic/plastic anisotropy in each phase may cause grain-to-grain interactions, which further modify the microscopic load partitioning between phases. In the current work, neutron diffraction experiments on the spectrometer for materials research at temperature and stress (SMARTS) were performed on an austenite-ferrite stainless steel for tracing the evolution of various microstresses during tensile loading, with particular emphasis on the load sharing among grains with different crystallographic orientations. The anisotropic elastic/plastic properties of the duplex steel were simulated using a visco-plastic self-consistent (VPSC) model that can predict the phase stress and the grain-orientation-dependent stress. Material parameters used for describing the constitutive laws of each phase were determined from the measured lattice strain distributions for different diffraction { hkl } planes as well as the laboratorial macroscopic stress-strain curve of the duplex steel. The present investigations provide in-depth understanding of the anisotropic micromechanical behavior of the duplex steel during tensile deformation.