2017 Volume 57 Issue 10 Pages 1851-1859
In this article, effects of carbide on the cooperative growth of pearlite have been explored based on a multi-phase field method. Optical microscopy observations of pearlite structure in eutectoid steels have been taken to validate the accuracy of the developed multi-phase field method. Besides, the simulation results are compared with the experimental results of Ridley and Frye, as well as the phase field simulation results of Steinbach, a good consistency has been found. Comparison results demonstrate that the growth morphology of pearlite is more accurate when the effects of carbide are considered. Influences of the carbide location and size have been considered to further analyze the cooperative growth of pearlite. Results demonstrate that the presence of carbide above the lamellar pearlite changes the growth situation by promoting the growth of cementite lamellar pearlite when it is just above lamellar cementite. Lamellar cementite in the vicinity of carbide easily melts off with the growth of lamellar pearlite, and the lamellar cementite evolves to form islands. Moreover, effects of different carbide diameter on the growth of lamellar pearlite have been explored. The final growth rate and growth morphology are basically the same despite variations in diameter. Relationship, which can be used to control the morphology and performance of lamellar pearlite, between the size of the carbide and the horizontal maximum bending distance have been obtained through statistical analysis of the transverse maximum bending distance of the lamellae.