An Act to promote the general welfare and stimulate the economy of the Commonwealth by requiring that all public bodies, including the Commonwealth, its political subdivisions, and all authorities, include in all contracts for construction, reconstruction, alteration, repair, improvement or maintenance of improvements of a permanent or temporary nature, a provision that if any steel products are to be used in the performance of the contract only steel products produced in the United States shall be used, and imposing liability for violation of this act.