NDE of Additively Manufactured Parts via Directly Bonded and Mechanically Attached Electromechanical Impedance Sensors

摘要

Additive Manufacturing (AM) allows increased complexity which poses challenges to quality-control (QC) and non-destructive evaluation (NDE) of manufactured parts. The lack of simple, reliable, and inexpensive methods for NDE of AM parts is a significant obstacle to wider adoption of AM parts. Electromechanical impedance measurements have been investigated as a means to detect manufacturing defects in AM parts. Impedance-based NDE utilizes piezoelectric wafers as collocated sensors and actuators. Taking advantage of the coupled electromechanical characteristics of piezoelectric materials, the mechanical characteristics of the part under test can be inferred from the electrical impedance of the piezoelectric wafer. Previous efforts have used piezoelectric wafers bonded directly to the part under test, which imposes several challenges regarding the applicability and robustness of the technique. This paper investigates the use of an instrumented clamp as a solution for measuring the electromechanical impedance of the part under test. The effectiveness of this approach in detecting manufacturing defects is compared to directly bonded wafers.