Extraction of Coupling Stiffness of Specimens Printed with Selective Laser Melting Using Modal Analysis

Modal analysis is an affordable form of nondestructive evaluation (NDE) for many forms of manufacturing. Developments in Additive Manufacturing (AM) have enabled the printing of sophisticated metal parts in processes like Selective Laser Melting (SLM). In most metallic AM processes fabrication is conducted on a build plate, which allows for convenient fixturing for model analysis. However, many build plate contain multiple parts that introduces the challenge of dynamic coupling where the dynamic characteristics of other specimens appear in the frequency analysis of the specimen that is being analyzed. The dynamic coupling can obscure the analysis, especially for prints with multiple identical parts. This work sets a foundation for a method to improve the modal analysis of multiple AM parts fabricated on a single build plate by estimating the coupling stiffness between two specimens with similar modal characteristics.