Session: 07-01: NDE for Additive Manufacturing / 03-01: Electromagnetic NDE Techniques

Paper Number: 147590

147590 - Towards Ultrasonic Characterization of Microstructural Properties in Additively Manufactured Ss316l Samples 

Abstract: 

Metal additive manufacturing (AM) enables the production of complex geometric products with multi-dimensional controllable parameters, offering numerous advantages. However, uncontrollable disturbance factors during the manufacturing process can influence microstructural characteristics, leading to uncertainties in mechanical properties. Mechanical properties are known to be governed by the microstructure, including grain morphology and texture. Current material characterization techniques, such as optical microscopy (OM), scanning electron microscopy (SEM), and Electron Backscatter Diffraction (EBSD), require careful material preparation. These testing procedures are both slow and tedious. Consequently, there is a pressing need for efficient, cost-effective, and non-destructive evaluation methods to characterize microstructural features in AM samples.

This work investigates the ultrasonic response in additively manufactured SS316L samples, especially when grains possess both intricate morphologies and pronounced textures due to the AM process. A finite element model is established to simulate ultrasonic wave propagation in the heterogeneous polycrystalline materials. Subsequently, the properties of ultrasonic waves, such as wave velocity and attenuation, are linked to the microstructural features, such as the aspect ratio of columnar grains or the intensity of texture. Moreover, a microstructural inhomogeneity parameter is explored to statistically correlate with both the elastic wave scattering properties in the ultrasonic simulation and the strain localization properties in the elastodynamic simulation.

Presenting Author: Zheng Fan Nanyang Technological University

Presenting Author Biography: Dr. Zheng Fan is an associate professor in the School of Mechanical and Aerospace Engineering at Nanyang Technological University, Singapore. He earned his Ph.D. degree in Mechanical Engineering from Imperial College London in 2010, and his Bachelor's and Master's degrees in Acoustics from Nanjing University in 2004 and 2006, respectively. Currently, he leads a research team dedicated to developing novel techniques for the non-destructive evaluation, structural health monitoring, and sound manipulation. His work integrates advanced physics and modeling techniques with the development of technologies that can be rapidly deployed in practical settings. Dr. Fan maintains strong links with the global industry, collaborating with major companies such as Rolls-Royce, Shell, Lloyd's Register, EDF, and Sembcorp, etc. His research spans from thorough investigations of fundamental theories to the application of science in addressing real-world challenges. The results of his work have been published in over 80 papers in top tier journals. He holds two international patents and has successfully licensed these technologies to industry partners. In 2018, Dr. Fan was awarded the Achenbach Medal for his outstanding contributions to structural health monitoring. In 2023, he was ranked among the world's top 2% of scientists by Stanford University. Dr. Fan also serves as an Associate Editor for "Structural Health Monitoring – An International Journal" and "Ultrasonics," two leading journals in his field.

Authors:

Zheng Fan Nanyang Technological University
Junfei Tai Nanyang Technological University
Shangzi Wu Xi'an Jiaotong University