Ultimate Tensile Strengths and Elastic Moduli at 20 K of Additively Manufactured PA840-GSL, A6061-RAM2, and AlSi10Mg

Abstract

The additive manufacturing (AM) of polymer matrix composites (PMCs) and metal matrix composites (MMC) systems presents novel opportunities for reducing the mass of aerospace vehicles. These solutions also have the potential to reduce the cost of terrestrial applications where cryogenic temperatures are present. To address this need, this paper explores the mechanical characterization of three AM materials at 20 K: a nylon-based PMC PA840-GSL, and two aluminum-based MMCs A6061-RAM2 and AlSi10Mg. A Cryogenic Accelerated Fatigue Tester (CRAFT) used for the mechanical testing is first detailed. Next, ultimate tensile strengths and elastic moduli of the additively manufactured AlSi10Mg alloy and A6061-RAM2 are obtained. Third, the mechanical performance of an additively manufactured PMC liquid hydrogen tank constituent is collected in addition to an analysis on the effect the processing parameters, such as scan spacing, have on the mechanical behavior. A6061-RAM2 exhibited superior mechanical performance and is recommended for structural applications. Variation of PA840-GSL scan spacing resulted in decreased mechanical performance.