Innovative Surface Modification for Aluminum, Magnesium and High Strength Steel Alloys to Enhance Corrosion Resistance

It is proposed to apply optimized surface treatment strategies to stainless steel identified from phase-I study to improve strength and corrosion resistance for wing-fold transmission (WFT) systems. During the six months of the phase I project, two material systems were considered for the preliminary study. These materials included: Custom 465 Stainless, and CSS 42L carburizing stainless steel. These materials have been processed for both low temperature carburization and thermo-mechanical processing (shot-peening) and it was discovered that CSS 42L meets all the requirements for NAVY application and custom 465 may require some refinement in the surface treatment. CSS 42L is a high-strength stainless steel that is intended explicitly for carburizing applications, and exhibits corrosion resistance suitable for applications such as the wing-fold transmission (WFT) system. The requested funding for Phase-II will be used to implement the series of heat treatment and carburization studies that has been discovered as part of phase-I to perform a complete analysis of the mechanical and corrosion characteristics of the resulting material. During phase I- option some of the procedures developed for the heat treatment will be refined and Phase II portion will be entirely invested on the implementation of these procedures.