A Review of Mechanical Properties Characterization and Structural Process Design for Needle‐Punched Fiber‐Reinforced Composites

ABSTRACT As a three‐dimensional reinforcement material with excellent interlayer properties, needle‐punched fiber‐reinforced composites have been increasingly widely used in aerospace, energy, automotive, and other fields in recent years. The fibers in the plane are introduced into the thickness direction by needle‐punching processes and form vertical fiber clusters; therefore, the material has both in‐plane and interlayer strength, as well as advantages such as low cost, short cycle time, and strong designability. However, the fiber damage caused during the needle‐punching process and the complex microstructure of the preform body make the needle‐punched composites extremely difficult, such as in mechanical properties characterization and structural process design. This article focuses on three aspects of research on the needle‐punched composites: needle‐punched preform forming processes, mechanical properties characterization, and structural and process design of needle‐punched composites. It analyzes the application of macroscopic mechanical experiments, microscopic structural characterization techniques, and numerical simulations for predicting the mechanical properties of needle‐punched composites. Meanwhile, it elucidates the influence of process parameters on mechanical properties and the research status of structural and process design based on experiments, finite element simulations, and machine learning methods. This article summarizes and condenses the research results, aiming to provide reference for the needle‐punched composites research and promote the application of this material in the engineering field.