COATING SYSTEM FOR HIGH TEMPERATURE TITANIUM ALLOYS

ADVANCE TITANIUM ALLOYS HAVE PROMISING POTENTIAL APPLICATIONS FOR FUTURE GAS TURBINE ENGINES USED IN NAVAL AIRCRAFTS AND MISSILES. HOWEVER, OXIDATION AND HOT SALT-INDUCED STRESS-CORROSION CRACKING, CREEP OR FATIGUE RESULTED IN SIGNIFICANT SURFACE DETERIORATION OF THESE ALLOYS. IN THIS PROPOSED STUDY, WE ATTEMPT TO TEST THE FEASIBILITY OF TWO NEW INORGANIC OXIDE POLYMERS AS PROTECTIVE LAYERS AGAINST THESE HAZARDS. THESE POLYMERS WILL FORM COVALENT BONDS WITH SUBSTRATE SURFACES, AND THE COATINGS ARE NON-PERMEABLE TO CORROSIVE GASES, OXIDATION RESISTANT, HIGH-EROSION AND HIGH TEMPERATURE RESISTANT. IN PHASE I STUDIES, FLAT COUPONS OF ADVANCE TITANIUM ALLOYS WILL BE COATED WITH THESE POLYMERS FOR PRELIMINARY TESTING OF THE FILM PROPERTIES. PHASE II WORK WILL INVOLVE FURTHER CHARACTERIZATION OF THESE COATINGS, VARIOUS MEANS OF SURFACE APPLICATIONS, AND THE POSSIBLE CONFIGURATIVE STRUCTURE OF MULTILAYER, MULTICOMPONENT OR COMPOSITE COATINGS. FINALLY, COATED COMPONENTS WILL BE SUBJECTED TO SIMULATED AND REAL ENVIRONMENTAL TESTINGS. THE SUCCESS OF THIS STUDY WILL PROVIDE SUBSTANTIAL BENEFITS TO DOD AND INFORMATION GENERATED ARE NEEDED BY BOTH CIVIL AND MILITARY SECTORS OF THE FEDERAL GOVERNMENT.