This article describes the formation of lined-up particles on the solid-gas surface by a moving grain boundary. Particles of cobalt-based solid solution are formed on the surface of copper-based solid solution. Grain boundary motion was induced by deforming a part of the sample. The particle growth kinetics was evaluated according to the data on the kinetics of thermal etching of grain boundary. The resulting lined-up particles are unstable and deaggregate into individual particles corresponding to the equilibrium state for the given facet. Linear tension of the grain boundary compensating for the strain caused by size misfit between the substrate and the particle was considered the reason why particles grow in the direction of grain boundary motion.