Elastoplastic deformation of 316 stainless steel under tensile loading at elevated temperatures

Abstract

The response of 316 stainless steel has been examined under uniaxial tensile loading during ar ange of tests carriedo ut between 20°Ca nd 650°C. In-situ neutron diffraction was used to measure internal elastic strain in subsets of differently oriented crystallites within the polycrystal aggregate. This allowed the determination of diffraction elastic constants. Further,r esults have been compared with predictions from as lip-based elasto-plastic self-consistent model. Good agreement is obtained during both conventional slip and whend ynamic straina ging (DSA) is evidenced. The quality of agreement was reduced in the higher temperature regime, where it is expected that other mechanisms become active.

Effect of boundary conditions on the evolution of lattice strains in a polycrystalline austenitic stainless steel

“…The diffraction elastic constants (DEC) for each plane were obtained by dividing the change in applied stress by the corresponding change in lattice strain for each plane during unloading and are summarised in Table 2. The elastic moduli obtained in the current study perfectly agreed with the work conducted by Daymond and Bouchard [6]. The lattice strains relaxed with the relaxation of applied stresses linearly during creep under Z * 1.2 and Z * 10.5 and act similar to unloading process, as shown in c. Therefore, the lattice strains were found to relax the most in the elastically softest lattice plane {200} and the least in the elastically stiffest lattice plane {111} due to different grain families in crystalline materials displaying elastic anisotropies.…”

“…It is well known that when a polycrystalline material undergoes macroscopic plastic deformation, intergranular strains or stresses can be generated within grain families as a consequence of elasticplastic anisotropy at the grain scale [6][7][8][9]. Creep as a time-dependent plastic deformation can also generate intergranular strains/stresses in Type 316H austenitic stainless steel often during primary stage of the constant load creep [10][11][12].…”

Microscale prediction of deformation in an austenitic stainless steel under uniaxial loading

“…Its single crystalline counterpart has shown significant elastic anisotropy (see Ledbetter, 1981). The three independent elastic constants, C 11 , C 22 , C 44 for 316H were obtained by Daymond and Bouchard (2006) from ND measurements and are adopted in the current study as shown in Table 2. The shear modulus, µ 0 at 0 K needed for the flow rule (Eqn.…”

“…The shear modulus, µ 0 at 0 K needed for the flow rule (Eqn. 4), was obtained by extrapolating the modulus data of Daymond and Bouchard (2006) 6 M A N U S C R I P T…”

“…As a non-destructive technique, neutron diffraction (ND) has been employed to explore in-situ the micromechanical deformation behaviour in terms of the evolution of lattice strains for differently oriented grain within a polycrystal under mechanical loading (see, e.g., Clausen M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT et al, 1998, 1999Daymond et al, 2000;Pang et al, 2000;Lorentzen et al, 2002;Daymond and Bouchard, 2006;Marin et al, 2008;. A description of techniques for strain measurement using ND is found in Hutchings et al (2005).…”