Title: Bonding to Bulk Metallic Glass Using Aerospace-Grade Structural Adhesive
Authors: Rose Roberts, Elizabeth Kidd, Evan Hilgemann and Giles Dillingham
Abstract: Bulk metallic glasses, also known as amorphous metals (AMs) are non-crystalline metals with growing applications in aerospace. Due to their amorphous nature, AMs generally exhibit stronger mechanical properties than most crystalline alloys and are more corrosion resistant. The limited reactivity of a corrosion resistant surface may explain the difficulty in establishing robust bonds to certain adhesives, especially commonly used structural adhesives for aerospace applications. Here, an amine cured aerospace adhesive was used for bonding an iron-nickel based AM satellite component. Various types of processes were explored to avoid adhesive failure and increase bond strength. It was found that the AM required specific chemical derivatization of the metal surface in order to achieve cohesive failure using the epoxy adhesive. Surface analysis was used to determine the mechanisms of adhesion enhancement. This work helps explain the difficulties in bonding AM materials and provides strategies for design of future bonded AM components.
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Conference: SAMPE 2020 | Virtual Series
Publication Date: 2020/06/01
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