3D finite element simulation of the inhibition of normal grain growth by particles

An original model to simulate single grain boundary motion and its interaction with particles (Couturier G, Maurice C, Fortunier R. Phil Mag 2003;83:3387) is applied to model curvature driven grain growth. For single phase material, the single grain boundary model closely matches the grain coarsening kinetics of a 3D multi boundary vertex model. In the presence of spherical incoherent particles the growth rate slows down to give a growth exponent of 2.5. When the boundary is anchored there is a significantly higher density, four times higher, of particles on the boundary than the density predicted by the classic Zener analysis, but particles exert, on average, a drag force about half of the maximum value assumed by Zener. As a result the Zener drag is increased by a factor of 2.2. The limiting grain radius is compared with some experimental results.