金属材料の高速衝撃引張試験
1963 年 32 巻 10 号 p. 731-742
詳細
1963 年 32 巻 10 号 p. 731-742
The uncertainty of yield load and ultimate load measurements in high-speed impact tension test of metallic materials is discussed. For obtaining the yield land within the error of 5%, the impact of up to 5m/s velecity is to be used. However, since the lower yield load appears distinctly flat on the load-time curve with impact velocities of up to 20m/s, such tests may not be meaningless if generous allowance is made for the error. As for the ultimate load, it drops significantly when the impact velocity exceeds 60m/s due to the effect of stress wave propagation.
The critical velocities obtained from the elongation drop and the change of strain distribution of fractured test pieces are compared with the respective values calculated by von Karman's method.
The effect of temperature on the deformation rate of tensile properties is described for mild steel, pure copper and pure magnesium with some remarks.
