Title: Quantification of Impact Damage to Carbon Composite Bicycle Tubes Using Phased Array Ultrasonic Testing and Photomicrographic Image Analysis

Authors: Shawn W. Small, Heather M. Wilson

DOI: 10.33599/nasampe/c.22.0044

Abstract: Barely visible impact damage (BVID) is a serious consideration in use of carbon fiber reinforced plastic (CFRP) as structural elements that may be subjected to impacts. A body of research exists on BVID in CFRP used in the automotive and aeronautical sectors, but little attention has been focused on internal damage to CFRP bicycle frame tubes produced by impacts that cause BVD. Internal damage to frames can lead to catastrophic failure and presents a serious safety hazard, but we have a limited understanding of the impact force required to produce significant damage. A drop tower was used for impact testing of CFRP tubes of a similar diameter and thickness to CFRP bicycle frame tubes. The drop height of the impactor was varied to produce BVID from a range of potential energies. Internal damage caused by each impact was quantified using phased array ultrasonic testing and photomicrographic image analysis of sections through the point of impact. After determining the relationship between impact energy and internal damage propagation, CFRP bicycle frame top tubes from a variety of manufacturers were drop impact tested to compare the results to the model tubes and extrapolate to damage expected from real-life impacts from a range of common bicycle tools.

References: 1. MIL-HDBK-17-3F. Composite Materials Handbook. Volume 3, Chapter 7, pp. 7–29. Arlington, VA, USA: US Department of Defense, 2002. 2. S. Chisholm, A. Rufin, B. Chapman, and Q. Benson. Forty years of structural durability and damage tolerance at Boeing Commercial Airplanes. Boeing Technical Journal, pp. 1–24, 2016. 3. ASTM D7136. Standard test method for measuring the damage resistance of a fiber-reinforced-polymer matrix composites to a drop-weight impact event, vol 15, Book of Standards, 2005.

Conference: CAMX 2022

Publication Date: 2022/10/17

SKU: TP22-0000000044

Pages: 11

Price: $22.00