Non-Destructive Evaluation of Composite Helmets Using IR Thermography and Ultrasonic Excitation

The paper presents selected results of non-destructive testing of composite helmets with deliberately introduced defects. Ultrasound pulsed infrared thermography was used for the tests. In order to determine the initial possibilities of this method, artificial defects made of Teflon featuring different area sizes and designed to simulate delamination were placed between layers of the aramid composite from which the helmet was made. The obtained results confirmed the effectiveness of the NDT method used in these tests.

Assessment of Ultrasonic Welds Using Pulsed Infrared Thermography

Ultrasonic metal welding is used in the automotive industry for a wide variety of joining applications, including batteries and automotive wire harnessing. During electric vehicle battery pack assembly, the battery cell tab and busbar are ultrasonically welded. Quality inspection of these welds is important to ensure durable packs. A method for inspection of ultrasonic welds is proposed using pulsed infrared (IR) thermography in conjunction with electrical resistance measurements to assess the structural and electrical weld integrity. The heat source distribution (HSD) was calculated to obtain thermal images with high temporal and spatial resolution. All defective welds were readily identifiable using three postprocess analyses: pixel counting, gradient image, and knurl pattern assessment. A positive relationship between pixel count and mechanical strength was observed. The results demonstrate the potential of pulsed thermography for inline inspection to assess weld integrity.