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

This proposal seeks innovative solutions to address the Navy’s needs to extend life and durability of its aircraft. It is proposed to apply surface treatment strategies for two important classes of materials: Custom 465 Stainless, and CSS 42L carburizing stainless steel. The former is a highly corrosion resistant high-strength precipitation hardening material that, nevertheless, will require surface hardening to enhance wear resistance. It is proposed to accomplish this through mechanical treatments such as peening before aging, and, low-temperature carburizing. The latter material is also 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. We request funding to conduct a preliminary analysis of the mechanical and corrosion characteristics of these two materials (Phase-I), and optimize the processing of them necessary for the WFT application (Phase-II). The goal is to identify materials and processes leading to a WFT component that meets mechanical requirements and does not require a separate scheme for corrosion control. The identification of the process parameters will lead to the development of multiscale models for strengthening in steels due to combined effects of surface hardening and heat treatment with higher corrosion resistance.