【摘要】 本文描述一种长杆高速冲击确定K1d的实验装置，提出在断裂时间tf＜τ（τ为试样固有振动周期）范围内确定动态断裂韧度K1d的原理与方法，给出包含冲击速度（v0）和冲击载荷（P（t））的K1d计算公式利用该实验装置和所给K1d计算方法在不同的冲击速度条件下，测得三种回火处理30MnCrNiMoB高强装甲钢的K1d，结果表明K1d随加载时间增加而增加更多还原

【Abstract】 A new assembly with a long impact bar for measuring the dynamic fracture toughness K1d under the condition of fast fracture is described in this paper. The basic principle and the method evaluating K1d under the condition of the fracture time tf being less than the oscillation period of the specimen (τ) are given which include not only the impact velocity but also the impact load. An example is presented for measuring K1d of high strength armour steel 30MnCrNiMoB quenched and tempered at 200 - 600℃. The results show that Kid increases　with the loading time under high velocity impact, which are similar to those of 4340 AVR steel reported.更多还原