Influence of Specimen Thickness on Charpy Impact Test Results

The impact absorbed energy and side expansion value of non-standard small size V-notch impact specimens were analyzed through Charpy pendulum impact test at different temperatures, and the influence of specimen thickness on the impact test results were studied combined with force-displacement curves. The results show that when the test temperature is higher than ductile brittle transition temperature, the impact absorbed energy is related to cross-sectional area of specimen, so it has a linear relationship with the thickness. When the temperature is lower than ductile brittle transition temperature, there is no obvious relationship between the impact absorbed energy and the thickness of specimen. There is no direct relationship between the thickness and the side expansion value, shear section rate of specimen. With the decrease of specimen thickness, the initial force of unstable crack propagation becomes smaller and smaller, which leads to the decrease of impact absorbed energy. The greater the thickness is, the more energy absorbed by specimen and the greater the maximum force in the impact process.