船用917钢抗冲击性能试验

无论金属材料或是非金属材料,其力学性能都是与应变率相关的.由于应变率历史效应以及在高速变形条件下产生绝热剪切带等不稳定性因素,使得材料对于高应变率响应的问题变得十分复杂,而一些实验方法则起到了重要作用.材料的本构关系是与水下爆炸等现象仿真研究的精度直接相关的,材料在高应变率下本构关系的确定,对水下爆炸等产生高应变率现象进行仿真研究具有重要意义.本文通过Hopkinson杆装置对船用917低磁钢进行了抗冲击性能研究,并由试验给出了仿真研究中适用的本构关系.

The Experiment Research of Steel 917 under Impact Load

The constitutional relations of materials are directly connected with the simulation precision of numerical research. Therefore, it is significant to get material's constitutional relations in the simulation of underwater explosion, which will generate high strain rate. The dynamic characteristic of materials is correlated with strain rate no matter what kind of materials they are, metallic or nonmetal-lic. Although the response to the high strain rate of materials is complicated, the problem can be solved by experiment in a certain extent. Low magnetic steel 917 is a kind of materials usually applied to the vessel structure of mine sweeper. The mine sweeper sails in the mine field so that the anti-explosion capability of steel 917 is especially significant. Static tension experiment and dynamic impact experiment with the support of the Hopkinson e-quipment have been conducted to get the general mechanical characteristic and dynamic characteristic of steel 917 respectively. There are two useful material models calculating underwater explosion. Considering the corresponding feature of the structure under dynamic impact load, the applicable constitutional relations in the simulation are obtained by the foregoing experiments. Compared with the results of the previous experiments some reasonable advice has been given as follows: (1) Under the condition of the 700 per second strain rate, the dynamic yield stress of steel 917 has increased 35%-40%. (2) Combined with the material models in FEM and the characteristic of underwater explosion, the parameters of steel 917 in two material models are offered. (3) The dynamic mechanics performance of steel 917 in high strain rate varies greatly compared with the mild steel. In the research of underwater explosion phenomena and otherwise, it is suggested that the reasonable parameters should be obtained by experiments.