QUALITY OF 3D PRINTED (ADDITIVE MANUFACTURING) MATERIALS: MICROSTRUCTURE, MECHANICAL PERFORMANCE, AND PROCESS OPTIMIZATION

 Additive manufacturing (AM), commonly known as 3D printing, has transformed modern materials engineering by enabling complex geometries, reduced material waste, and rapid prototyping. Despite these advantages, the quality of AM-produced materials remains a critical challenge, influenced by microstructural heterogeneity, porosity, residual stresses, and anisotropic mechanical behavior. This paper provides a comprehensive review of the factors affecting the quality of metallic, polymeric, and composite 3D printed materials. Key microstructural characteristics, process parameters, post-processing techniques, and quality assessment methodologies are analyzed. Strategies for optimizing material performance through parameter control, heat treatment, and surface finishing are discussed. Emerging approaches such as in-situ monitoring, machine learning-based process optimization, and multi-material printing are evaluated. The study concludes with perspectives on future research directions to achieve high-quality, reliable AM components suitable for aerospace, biomedical, and industrial applications [1].