A material removal method comprises receiving a component that includes a component body and a coating on the component body, the component body comprising metallic first material, and the coating comprising a second material that is different from the first material, wherein the component is a component of an item of rotational equipment. The method also includes receiving a solution comprising nitric acid and hydrogen peroxide and subjecting at least a portion of the coating to the solution in supercritical condition in order to remove at least some of the second material from the component, wherein a chemistry of the solution is selected such that the solution is substantially non-reactive with the first material.