Metal parts made through additive manufacturing can suffer from hidden flaws such as cracks and pores that compromise their performance and safety. These defects increase the production cost and limit the use of additive manufacturing in critical applications, such as aerospace, biomedical, and automotive systems. This Engineering Research Initiation (ERI) project aims to develop a real-time, non-destructive method for detecting internal defects using electromagnetic waves during the manufacturing process itself. By doing so, the research enables instant quality assurance without interrupting production or damaging parts. This will make additive manufacturing more reliable, cost-effective, and suitable for widespread use. The project will also contribute to building a skilled workforce through educational outreach, curriculum development, and research training for students. These efforts are aligned with the national goals of advancing science, strengthening domestic manufacturing, and maintaining the nation's global competitiveness. Ultimately, this research aims to transform the way advanced materials and components are inspected, thereby improving safety, reducing waste, enhancing the supply chain, and supporting innovation. The primary goal of this research is to develop a physical framework that links the behavior of electromagnetic signals to the shape, size, and location of defects in metal parts fabricated using laser powder bed fusion. The project will focus spec