Fatigue behavior of additively manufactured meta-biomaterials for biomedical applications: A review

Abstract

Metamaterials are engineered materials with unique properties arising from their structure rather than composition, featuring repeating patterns smaller than the wavelengths they affect. Meta-biomaterials are an important subset of metamaterials and have drawn increasing interest in recent times due to their favorable mechanical properties, biological properties and functional integrity. These exceptional properties have enabled their suitability for diverse biomedical applications, including orthopedic/dental implants, tissue engineering, and medical devices. These materials are generally subjected to cyclic musculoskeletal loads after implantation, making the study of their fatigue behavior critical for ensuring long-term reliability. The current review, therefore, focuses on the fatigue behavior of meta-biomaterials that are manufactured using different additive manufacturing techniques. Various factors like topological design, base material/alloy selection, type of fatigue loading, manufacturing and secondary treatment processes, etc., are carefully analysed, and their influence on fatigue performance is studied. Furthermore, the failure mechanisms of additively manufactured meta-biomaterials with different geometries, structures, and architectures are also analyzed. Thus, this comprehensive review not only elucidates the underlying fatigue mechanisms, but also establishes a framework for the rational design of next-generation of biomedical implants with enhanced durability and functionality.