Nylon material usually suffer dynamic load when it is used in gear, shaft roller and aviation devices. Therefore, the study of the mechanical properties of nylon materials under static and dynamic loads is necessary. By using the MTS810 material testing machine and the SHPB experimental device, the quasi-static compression test and dynamic compression test of nylon (PA) were carried out and the stress-strain curve of nylon material was obtained. The results show that the yield stress growswith the increase of the strain rate. Compared with static compression, dynamic compression softening effect is weakened, and it is replaced by the following reinforcement effect, which indicates the existence of competitive trend of strain softening and strain hardening under high strain rate. The material parameters are obtained by using the Cowper-Symonds stress model combined with the experimental data and the theoretical curves are fitted, maximum error of the result is respectively 2%, 1%, 7%, has good agreement with the experimental results.%尼龙材料在用作齿轮、辊轴、航空器件等情况下需承受动态荷载,因此研究尼龙材料在静、动态荷载下的力学性能是有必要的.利用MTS810材料实验机和SHPB实验装置,开展尼龙(PA)的准静态压缩实验和动态压缩实验,通过实验获得尼龙材料的应力应变曲线.结果表明:尼龙材料在压缩时,随着应变率的增大屈服应力逐渐增大.与静态压缩相比,动态压缩软化效应减弱,而被随后而至的强化效应所取代,表明高应变率下应变软化和应变硬化存在竞争趋势.采用Cowper-Symonds过应力模型结合实验数据获得尼龙的材料参数并拟合理论曲线,其结果与实验结果的最大误差分别为2%,1%,7%,吻合较好.
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