Grain growth characteristics of plasma-sprayed nanostructured Al2O3-13wt.%TiO2 coatings during laser remelting

Nanoparticle growth during laser remelting was studied to provide references for optimizing technological parameters. The variations of nanoparticle sizes during laser remelting plasma-sprayed presetting of nanostructured Al2O3-13 wt%TiO2 coating were investigated on the basis of the classical theories of grain growth and by combining the temperature courses of nanoparticles at different positions, which were obtained from laser remelting finite element numerical simulation of the temperature field. Moreover, the effects of initial nanoparticle size and different remelting positions on grain growth were analyzed. A laser remelting test was conducted on the corresponding plasma-sprayed nanostructured coating. Results show that the overall trend of nanoparticle growth in the laser remelting test is consistent with theoretical calculation results, indicating that the classical theory of grain growth can offer some theoretical guidance to understanding nanoparticle growth during laser remelting.