A method for strengthening a glass article. The method includes exposing a selected area of the glass article to a beam of electromagnetic radiation in order to diffuse first alkali metal ions in the selected area out of the glass article and to diffuse second alkali metal ions on a surface of the glass article and in the selected area into the glass article. The second alkali metal ions are larger than the first alkali metal ions. The beam of electromagnetic radiation heats first alkali metal ions and the second alkali metal ions to a temperature that is greater than that of a glass network of the glass article.