Abstract
Additive manufacturing has enabled the fabrication of metallic components with complex geometries and enhanced design flexibility, expanding the applicability of advanced structural alloys. In this context, the production of metastable β-titanium alloys via laser powder bed fusion (LPBF) has attracted growing interest due to their high specific strength, excellent toughness, and superior fatigue resistance. Among these alloys, Ti-5Al-5Mo-5V-3Cr (Ti5553) has emerged as a promising candidate for critical aerospace components, including landing gear systems, which are routinely subjected to high strain-rate loading conditions. In cold-climate regions, such as Canada, landing gear structures may additionally experience dynamic loading at reduced temperatures, making the understanding of sub-ambient high-rate deformation behavior particularly important. In this study, the dynamic compressive response of LPBF-Ti5553 was investigated under high strain-rate impact loading at room and sub-ambient temperatures. The results indicate that reducing the testing temperature leads to a measurable increase in compressive strength, while the overall deformation capability remains largely unchanged. This combination of enhanced strength retention and stable ductility under sub-ambient dynamic conditions highlights the alloy’s suitability for impact-critical applications operating in cold environments. Microstructural examinations revealed that plastic deformation at sub-ambient temperatures is primarily accommodated through dislocation-mediated slip during high strain-rate loading. These findings provide insight into the low-temperature dynamic performance of additively manufactured Ti-5553 and support its potential use in aerospace components subjected to impact loading in cold service conditions.