One aspect of the invention is a method of surface alloying stainless steel, In one embodiment, the method includes providing a stainless steel surface having an initial amount of iron and an initial amount of chromium; and preferentially removing iron from the stainless steel surface to obtain a surface having an amount of iron less than the initial amount of iron and an amount of chromium greater than the initial amount of chromium. Another aspect of the invention is a unitary stainless steel article.