试样厚度对夏比冲击试验结果的影响

通过不同温度下的夏比摆锤冲击试验对非标准小尺寸V型缺口冲击试样的冲击吸收能量和侧膨胀值进行了分析,并结合力-位移曲线,研究了试样厚度对冲击试验结果的影响。结果表明:当试验温度高于韧脆转变温度时,冲击吸收能量与试样的横截面积有关,因此与厚度呈线性关系;而低于韧脆转变温度时,冲击吸收能量与试样厚度之间没有明显关系;试样的侧膨胀值、剪切断面率与厚度之间没有直接联系。随着试样厚度的减小,不稳定裂纹扩展起始力越来越小,从而导致冲击吸收能量减小。厚度越大试样吸收的能量越多,冲击过程中所受到的最大力也越大。

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.