TY - JOUR T1 - Analysis of Internal Crack Healing Mechanism under Rolling Deformation A1 - Gao, Haitao A1 - Ai, Zhengrong A1 - Yu, Hailiang A1 - Wu, Hongyan A1 - Liu, Xianghua Y1 - 2014/07/08 N2 - A new experimental method, called the ‘hole filling method’, is proposed to simulate the healing of internal cracks in rolled workpieces. Based on the experimental results, the evolution in the microstructure, in terms of diffusion, nucleation and recrystallisation were used to analyze the crack healing mechanism. We also validated the phenomenon of segmented healing. Internal crack healing involves plastic deformation, heat transfer and an increase in the free energy introduced by the cracks. It is proposed that internal cracks heal better under high plastic deformation followed by slow cooling after rolling. Crack healing is controlled by diffusion of atoms from the matrix to the crack surface, and also by the nucleation and growth of ferrite grain on the crack surface. The diffusion mechanism is used to explain the source of material needed for crack healing. The recrystallisation mechanism is used to explain grain nucleation and growth, accompanied by atomic migration to the crack surface. JF - PLOS ONE JA - PLOS ONE VL - 9 IS - 7 UR - https://doi.org/10.1371/journal.pone.0101907 SP - e101907 EP - PB - Public Library of Science M3 - doi:10.1371/journal.pone.0101907 ER -