Effect of interlamellar spacing on the elastoplastic behavior of C70 pearlitic steel: Experimental results and self-consistent modeling

The effect of pearlite microstructure characteristics on strength and deformation of C70 pearlitic steel was investigated. Tensile tests under X-ray diffraction coupled with self-consistent model have been used to identify the role of interlamellar spacing on the ferrite plasticity parameters and residual stress induced by plasticity. Tests have been carried out on two pearlitic microstructures with interlamellar spacing Sp = 170 and 230 nm respectively. Ferrite critical shear stresses ðs0c ðaÞÞ are equal to 75–86 MPa for interlamellar spacing Sp = 230 nm and 105–120 MPa for interlamellar spacing Sp = 170 nm. Moreover, the compressive residual stress measured in ferrite phase is higher in elasto-plastically deformed sample (total strain of E11 = 1.2%) having larger interlamellar spacing (rR Fea ¼ 161 MPa for Sp = 230 nm and rR Fea ¼ 77 MPa for Sp = 170 nm)

Effect of Interlamellar Spacing on the Monotonic Behavior of C70 Pearlitic Steel

International audienceThe effect of interlamellar spacing on monotonic behavior of C70 pearlitic steel was investigated. Tensile tests under X-ray diffraction coupled with self-consistent model have been used to identify the role of interlamellar spacing on the ferrite plasticity parameters and residual stresses. It has been established that yielding of pearlite is controlled by ferrite critical shear stresses ( τc 0α) which is higher for the smaller interlamellar spacing. Moreover, the residual stress level in ferrite is higher for the largest interlamellar spacing under the same imposed total strain. Lattice strains, measured by synchrotron X-ray diffraction, show an elastic and plastic anisotropy of ferrite crystallites and high stresses in cementite which confirm the self-consistent model calculation

Study of Mechanical Behaviour of Polycrystalline Materials at the Mesoscale Using High Energy X-Ray Diffraction

International audienceOwing to its selectivity, diffraction is a powerful tool for analysing the mechanical behaviour of polycrystalline materials at the mesoscale, i.e. phase and grain scale. In situ synchrotron diffraction (transmission mode) during tensile tests and modified self-consistent elastoplastic model were used to study elastic and plastic phenomena occurring in polycrystalline specimens during deformation. The evolution of stress for grains which belong to different phases of duplex stainless steel and pearlitic steel was analyzed