In a macro-scale material point, the microstructure, with ranging grain configurations and crystal orientations, govern material properties. Under stress, heat, or boundary shifts, the grains produce various material responses against these factors over time. Due to computational cost considerations, a representative volume element (RVE) is often selected from the domain to represent the entire domain in its behavior. The size of the element and its boundary conditions are much significant in the outcome. The main goal of this study is to reveal the effects of the size of the RVE and boundary conditions namely periodic, symmetry and micro hard on convergence and the results of a 2D phase-field model with stressed grain growth. For this purpose, the size of the RVE in a polycrystalline metal was adjusted in the 50–1000 ?m range, investigating grain growth under the explained boundary conditions with an elastic strain applied in uniaxial tension to find the optimal RVE size. Based on simulation results and their comparison with analytical results, the optimal RVE size was found to be 300 µm under the periodic boundary condition, 500 µm under symmetry boundary condition and 700 µm under micro hard for stressed grain growth. Based on the results obtained and compared with microstructures it can be noted that periodic and symmetry boundary conditions are more ideal for grain growth than micro hard boundary condition. Keywords: RVE, Polycrystalline, Boundary condition, Grain Growth, Phase Field
