Ultrasonic testing of composite materials damaged by lightning strikes

• Main Author: Hah, Alvin Hong Yang
• Other Authors: Li Lin
• Format: Final Year Project
• Language: English
• Published: 2019
• Subjects: Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/78762
• Institution: Nanyang Technological University

Currently the aerospace and manufacturing industries are excessively involved with Composites as their main materials for the construction of parts. During operations, composites are prone to heat damaged that may result in delamination and debonding. After a long period of time , the composites will lose its strength properties and eventually lead to fatigue failure which is undesirable. Conventional ultrasonic testing (C-scan) can be done to locate such defects. This report will emphasize the detrimental effect of lightning strike on variable composites. Internal damage are not apparent to our naked eyes and it can only be determined by Non-destructive test like C-scan. The results obtained will show the internal damage done by different heating temperature and multiple heating. Undamaged composites are also scanned to have a comparison and also to test the integrity of the ultrasonic machine. Damage through heating with a heat gun is simulated to the actual lightning strike. Thus the heat of 1500 degree Celsius was used to heat the composites at different timing and repeated heating. Characteristics of defect areas and non-defect areas would be discussed. Results would be presented in this report with images and qualitative and quantitative analysis where applicable. This study also aims to compare the external damage with the internal damage