Defect detection for remanufacturing engineering using non-destructive testing

• Main Author: Yeo, Hwee Ling
• Other Authors: School of Mechanical and Aerospace Engineering
• Format: Final Year Project
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/60996
• Institution: Nanyang Technological University

Coating technologies are extensively used in various remanufacturing and repair purposes. However, there is little knowledge on the material properties of the coating. These properties are mostly obtained by destructive testing means which are uneconomical. In this project, operating procedures are clearly developed and have proven to be effective in defect detection and obtaining of material properties through Scanning Acoustic Microscopy (SAM), a non-destructive way of testing. Defect characterization is done for both Ni-5%Al and AISI 4340 samples and is very conclusive and beneficial for future application. Material properties of the Ni-5%Al coating, which include thickness, longitudinal velocity, impedance and elastic modulus are evaluated and yield a reliable value. Most importantly, an accuracy of 20 microns is achieved for the thickness derivation. Also, defects of down to a few microns in diameter can be easily detected without fail. All the defects detected agree closely to the findings in the literature review.