Fracture Observation in Glass Ring-on-Ring Bending Tests Using HPV-X3

User Benefits

- The HPV-X3 high-speed video camera has a resolution three times higher than conventional models, allowing for high-resolution, high-speed imaging. - The HPV-X3 makes it possible to observe the origin of glass fractures and the propagation of cracks while allowing high-speed imaging at a maximum of 20 Mfps.

Introduction

In recent years, glass is being used in a diverse range of applications, including electronics, automobiles, and architecture. For example, smartphone screens and automobile windshields demand high-strength glass, so three-point bending tests, four-point bending tests, and ring-on-ring bending tests are used to evaluate strength. In three-point and four-point bending tests, the results depend on the condition of the edges since cracks at the edge of the test piece can become the origin of a fracture. On the other hand, the ring-on-ring bending test is considered a biaxial four-point bending test, and it can evaluate the ‘in-plane strength’ of glass without being influenced by the edges. This test is specified in ASTM C1499, and the pass or fail judgment is determined by observing the origin of the fracture on the specimen with tape applied to the compression side. Accordingly, it is important to not only perform the test but also to confirm the origin of the fracture. In a previous report, the fracture process of strengthened glass in a ring-on-ring bending test was observed using the HPV-X2 high-speed video camera. The newly developed HPV-X3 has a resolution three times higher than the HPV-X2, allowing for more detailed observation of glass cracks.

June 3, 2025 GMT