采用仪器化冲击试验方法对核电材料用钢SA508 Gr.3-Cl.2进行夏比冲击试验, 记录其冲击过程的力-位移曲线, 然后按GB/T 19748-2005中附录C提供的方法计算该钢的剪切断面率, 并与传统测量方法所得的数据进行比较。结果表明: 采用GB/T 19748-2005附录C中的公式(C.3)计算得到的剪切断面率数值与实际测量值之间具有较好的吻合性; 相同条件下, 高韧性试样的实测值与计算值的吻合性要高于低韧性试样的; 当公式(C.3)中的系数K=0.43时, 该公式为计算SA508 Gr.3-Cl.2钢剪切断面率的最优化公式。

Charpy impact test was done to nuclear steel material SA508 Gr.3-Cl.2 by using instrumented impact test method, and the force-displacement curve during the process was recorded. The percent shear fracture of the material was calculated by using formulas provided in annexes C of GB/T 19748-2005, and then the calculated values were compared with the data obtained by using the traditional measurement method. The results show that it was consistent between the calculated data obtained from formula (C.3) in GB/T 19748-2005 and the actual measured data. The calculated data of high ductile specimens showed a more conformity to the actual measured data than those of low ductile specimens under the same condition. It would be the optimum in calculating percent shear fracture of SA508 Gr.3-Cl.2 steel when the factor K in the formula (C.3) equals to 0.43.