新型ZrTiAlV合金力学性能及高速冲击行为研究

王爱民 张海峰 龚自正

摘要：ZrTiAlV合金具有较低的密度和优异的力学性能，使其有可能代替传统材料作为空间活动构件的新型材料使用。本文通过分离式霍普金森压杆、二级轻气炮和激光驱动飞片等实验技术，系统研究了ZrTiAlV合金的准静态和动态力学性能，冲击压缩性能和微小碎片高速撞击特性。研究发现，该合金具有较高的强度和较好的塑性，屈服强度随应变速率的提高而增加，变形过程中有塑性应变现象。通过热处理可以改善ZrTiAlV合金的力学性能。高温退火后合金完全由β相组成，在准静态和动态条件下均具有较好的塑性；退火后再回火可在β相中析出细小的α相，从而提高合金的强度，但经回火处理后合金在较高应变速率下塑性较差。经9MeV质子辐照后，ZrTiAlV合金的动态压缩强度随质子累积注量的增加而下降，经累积注量1×10 13/cm 2质子辐照后，合金的动态压缩强度随应变速率的增加而减小，而原始锻造态的合金动态压缩强度随应变速率的增加而增加，合金的塑性较差，且辐照前后的变化不大。通过冲击压缩实验，得到了ZrTiAlV合金的冲击波速度和波后粒子速度的关系，获得了该合金的Grüneisen参数和P-V-T物态方程。获得了微小碎片对ZrTiAlV合金单次和累积撞击损伤规律，分析了损伤机理。

关键词：ZrTiAlV合金；动态力学性能；热处理；质子辐照；冲击压缩；微小碎片高速撞击

Abstract：ZrTiAlV alloys have low density and excellent mechanical properties， making it possible to replace traditional materials as moving components in spacecraft. In this report， split Hopkinson pressure bar， two-stage light-gas gun and laser-driven flyer technology and some other experimental techniques were used to study systematically the quasi-static and dynamic mechanical properties， shock compression and micro-debris hypervelocity impact features of ZrTiAlV alloy. It was found that this alloy has high strength and good ductility， its yield strength increase with increasing strain rate， and plastic strain was found during deformation process. The mechanical properties of ZrTiAlV alloy can be improved by heat treatment. After high temperature annealing， the alloy was composed entirely of β phase， and have good plasticity under both quasi-static and dynamic conditions. After tempering， fine α-phase precipitates in β phase， thereby the strength was enhanced but ductility is poor especially at high strain rate. After irradiation by 9MeV proton， the dynamic compressive strength of ZrTiAlV alloy decrease with increasing proton cumulative fluence. After irradiation by proton with cumulative fluence of 1×10 13/cm 2， the dynamic compressive strength of the alloy decreased with increasing strain rate， however it increased with strain rate in original as-forged state. The plasticity of the alloy changed little before and after irradiation. The relationship between the shock wave velocity and particle velocity， Grüneisen parameters and PVT equation of state were obtained by shock compression experiments. The damage law of single and cumulative impact of micro debris on ZrTiAlV alloy was acquired and the damage mechanism was analyzed.

Keywords：ZrTiAlV alloy； Dynamic mechanical properties； Heat treatment； Proton irradiation； Shock compression； Micro debris hypervelocity impact

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