United States Steel and Security Act of 2012 - Amends federal provisions requiring the Department of Defense (DOD) to procure strategic materials critical to national security from materials produced in the United States (Buy American requirements) to include within the definition of "produced" that which is melted or processed in a manner that results in physical or chemical property changes that are the equivalent of melting. Excludes from such term finishing processes such as rolling, heat treatment, quenching, tempering, grinding, or shaving.