中低速冲击作用下316LN不锈钢板失效模式与吸能特性研究

Study on Impact Energy Absorption Characteristics of 316LN Stainless Steel Plate Under Medium and Low Speed Impact

核电管道因自身结构的重要性,对其抗冲击性能的研究显得尤为重要。因此,研究主要用材为316LN不锈钢的管道在冲击作用下的吸能特性具有重大意义。为探究在中低速冲击作用下不同头部形状的冲头对316LN不锈钢板失效模式与吸能特性的影响,本研究利用高速拉伸机开展了6.5~10 m/s冲击速度下,直径19.9 mm平头、半球形头和卵形冲头对1.5 mm厚的316LN不锈钢板的冲击穿刺试验,得到冲击载荷—时间曲线及靶板的失效模式。研究结果表明,靶板的失效模式、极限冲击载荷和冲击载荷历程均与冲头的头部形状密切相关,在采用半球形头、平头和卵形头冲头冲击时,靶板依次发生蝶形破坏、剪切冲塞和花瓣开裂,极限载荷分别为50 kN、39 kN和10 kN。但当冲头头部形状相同时,极限载荷对冲击速度不敏感。

Because of the importance of nuclear power pipeline structure, the study of its impact resistance is particularly important. Therefore, it is of great significance to study the energy absorption characteristics of 316LN stainless steel pipes under impact. In order to investigate the influence of punch with different head shapes on the failure mode and energy absorption characteristics of 316LN stainless steel plate under medium and low velocity impact, in this study, the impact puncture tests of 316LN stainless steel plates with a thickness of 1.5 mm were carried out by using flat, hemispherical and oval punches with diameter of 19.9 mm under impact velocity and the impact load-time curve and the failure mode of the target plate were obtained. The results show that the failure mode, ultimate impact load and impact load history of the target plate are closely related to the head shape of the punch. When the hemispherical, flat and oval head punches are used for impact, butterfly failure, shear plugging and petal cracking occur successively, and the ultimate loads are 50 kN, 39 kN and 10 kN, respectively. But when the punch head shape is the same, the limit load is not sensitive to the impact velocity.