Study of stress localisation in polycrystalline grains using self-consistent modelling and neutron diffraction

• Published in: Philosophical magazine (Abingdon, England) England), 2012-08, Vol.92 (24), p.3015-3035
• Main Authors: Baczmański, A., Gaj, A., Le Joncour, L., Wroński, S., François, M., Panicaud, B., Braham, C., Paradowska, A.M.
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Elasticity, elastic constants; Engineering Sciences; Exact sciences and technology; Instruments for strain, force and torque; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mechanical and acoustical properties of condensed matter; Mechanical instruments, equipment and techniques; Mechanical properties of solids; Mechanics; Mechanics of materials; multiscale modelling; neutron diffraction; Neutron diffraction and scattering; Physics; plastic deformation; polycrystalline metal; Single-crystal and powder diffraction; stress-strain measurement; Structure of solids and liquids; crystallography
• ISSN: 1478-6435; 1478-6443; 1478-6433
• DOI: 10.1080/14786435.2012.683542

The time-of-flight neutron diffraction technique and the elastoplastic self-consistent model were used to study the behaviour of single and multi-phase materials. Critical resolved shear stresses and hardening parameters in austenitic and austenitic-ferritic steels were found by analysing the evolution of the lattice strains measured during tensile tests. Special attention was paid to the changes of the grain stresses occurring due to transition from elastic to plastic deformation. Using a new method of data analysis, the variation of the stress localisation tensor as a function of macrostress was measured. The experimental results were successfully compared with model predictions for both phases of the duplex steel and also for the austenitic sample.