INSPECTION

The Non Destrutive Testing (NDT) technique used will depend on the specific defects identified. Methods like ultrasound (UT) or Thermography (IR) may be good for detecting delamination and voids but may not be a suitable inspection technique for cracks or un-bonding. Through 30 years of NDT experience, we have found x-ray is the most reliable inspection technique in detecting stress cracks and structural damage due to high and low speed impacts.

Computed Radiographic (CRT) x-ray testing is the most common method used for detection of cracks and other catastrophic structural inconsistencies. CRT can detect cracks and stress cracking, voids and porosity, inclusions, trans-laminar cracks, resin-to-fiber ratio, non-uniform fiber distribution and fiber misorientation, such as fiber folds, wrinkles or weld lines. Although delamination typically can be seen in a conventional CRT only if their orientation is not perpendicular to the X-ray beam.

Infrared Pulse thermography (IR) uses short pulse to excite the area of concern and then the cooling process is analyzed. The advantage of this method is the speed of the analysis and a possibility to estimate the depth of the defects. The disadvantage is a limited depth of the analysis and the inconsistency in respect to low and high speed impact.

Ultrasonic inspection (UT) can be used to detect anomalies such as delamination, porosity, voids, and bonding in composite laminates. Ultrasonic testing can be used on composites with less resolution but would not be best practices for any structural damage caused by low or high speed impact.

Acoustic inspection (the quarter test) is not a recognized inspection technique but a great down and dirty way for the potential customer to determine if there is any seen or unseen damage due to impact. Dull sound not good, sharp sound better but unless you’re a dog, an x-ray is a better NDT technique used with a long history in mission critical applications in the aerospace, automotive and sports industries.

Who is using these technologies? The aerospace industry uses CRT widely for wing, fuselage and engine components. The automotive industry has used CRT and CT since the 1990s, and sporting goods companies have adopted it as well. Professional cycling teams use X-ray inspection to ensure the performance of their composite equipment as well as manufacturers of composite baseball bats and tennis rackets to maintain quality control standards.

Spyder Composites has a long history and has pioneered the use of x-ray in determining failure causes and remediation in cycling substructures and components. With a high level of expertise and over 30 years experience in radiographic flaw detection in composite materials, we have adapted a best practices methodology to flaw detection that can lead to catastrophic failure in cycling components. Since 2006 we have imaged over 40,000 composite test objects from cycling to automotive, aerospace and marine. As an ISO 9000 certified shop and at the request of our clients we have used UT and IR for testing but have determined the gold standard is CRT and is our go to for low and high speed impacts.