钛合金J-C动态本构参数高精度分析及抗弹性能研究

High-precision analysis of J-C dynamic constitutive parameters of Ti alloy and research on its ballistic performance

摘要:

高速冲击下金属材料动态力学行为和变形局域化即绝热剪切变形的研究对材料在冲击环境下科学应用具有重要的意义。针对工程材料在大应变、高应变率和高温环境等应用条件,J-C本构方程是一种有效的处理手段。本文利用 “材料J-C本构参数及损伤模型参数测定系统”软件,通过聚类全局优化法获得一种近α型钛合金材料的J-C动态本构参数,规避了传统测定方法计算量大、方法复杂,且无法体现参数关联性等缺点；通过钛合金靶板的抗弹性能测试,利用J-C本构参数,采用商业动力学计算软件AUTODYN对枪击试验完成了模拟,模拟的各项结果与试验数据吻合度高,验证了J-C动态参数的准确度和精确性；通过弹孔显微组织分析可知在裂纹的末端可以观察到绝热剪切带,证明裂纹的萌生是由绝热剪切带引起,表明高速冲击动态环境下的失效模式主要为绝热剪切。

Abstract:

The research on the dynamic mechanical behavior and deformation localization of metals under high-speed impact, that is, the adiabatic shear deformation, is of great significance to the scientific application of materials under impact environments. J-C constitutive equation is an effective method to deal with the problems of large strain, high strain rate and high temperature of engineering materials. The software " J-C constitutive parameter and damage model parameter measurement system of materails -C dynamic constitutive parameters of a near α Ti alloy by clustering global optimization method, which avoids the large amount of calculation and complexity of traditional measurement methods and even can not reflect the shortcomings such as parameter relevance. Through the anti-elasticity test of the titanium alloy target plate, using the J-C constitutive parameters, the commercial dynamics calculation software AUTODYN was used to complete the simulation of the shooting test. The simulation results are in good agreement with the test data, which verifies accuracy and precision of the accuracy of the J-C dynamic parameters. Bullet hole microstructure analysis shows that adiabatic shear bands can be observed at the ends of the cracks, which proves that the initiation of cracks is caused by adiabatic shear bands, indicating that the failure mode under high-speed impact dynamic environment is mainly adiabatic shear.