In one embodiment, a method for forming an article with a diffusion portion comprises: forming a slurry comprising chromium and silicon, applying the slurry to the article, and heating the article to a sufficient temperature and for a sufficient period of time to diffuse chromium and silicon into the article and form a diffusion portion comprising silicon and a microstructure comprising α-chromium. In one embodiment, a gas turbine component comprises: a superalloy and a diffusion portion having a depth of less than or equal to 60 μm measured from the superalloy surface into the gas turbine component. The diffusion portion has a diffusion surface having a microstructure comprising greater than or equal to 40% by volume α-chromium.