Instrumented Charpy impact test: review and future directions

The conventional Charpy impact test provides a single primary measure of material performance: the total energy absorbed during fracture. When strain gauges or piezoelectric sensors are incorporated into the striker, however, the test can record force as a function of time and displacement throughout the impact. These measurements provide a more detailed picture of how a material responds and fractures under dynamic loading. The conventional Charpy impact test provides a single primary measure of material performance: the total energy absorbed during fracture. However, by incorporating strain gauges or piezoelectric sensors into the striker, the test can provide continuous force-time and force-displacement data throughout the fracture event, offering substantially more detailed information on the material’s dynamic fracture behavior. This review traces the development of the instrumented Charpy impact test from its early twentieth-century origins to its current applications. The fundamental principles underlying the measurement are described, with particular emphasis on the characteristic forces identified from the force-displacement curve and their physical significance. The final section of this review considers emerging works that may push instrumented Charpy testing further. Among the most promising directions are machine learning and artificial intelligence, digital twin technology, robotic automation, and high-speed digital image correlation (DIC).