Surface engineering of corrosion, environmental fracture, cavitation & impingement resistant materials

There is a need for materials that are highly resistant to corrosion, environmental fracture, cavitation, and liquid droplet impingement, especially within the Navy. Several novel approaches to enhancing the cavitation and impingement resistance of ship and aircraft components are discussed. These approaches include: (1) new ultra-hard amorphous-metal coatings, applied with a hydrogen-fueled HVOF process; (2) coatings with extreme interfacial bond strength, produced with LLNL’s new laser-based HVLAD process; (3) nickel aluminide coatings with nano-diamond strengthening and hardening, applied with a combination of cold spray and post- deposition heat treatment with intense diode sources; (4) diode-assisted friction stir processing for the elimination of surface defects in large cast propellars; and (5) laser peening for the elimination of residual tensile stresses, and the associated fatigue and environmental cracking. This paper discusses several novel approaches to the development of such materials, through surface engineering, and the benefits that will be enjoyed if such a developmental effort is successful.Department of Energy (DOE)Contract DE-AC52-07NA2734