【作者】 佘金虎；

【导师】 汤文辉；

【作者基本信息】 国防科学技术大学 ， 力学， 2009， 博士

【摘要】 本文以新型多薄层组合材料在脉冲X射线辐照下的热-力学效应为研究目标,对TC材料和GC材料准静态和动态力学性能及热物理性能进行了实验测量,建立了多薄层材料的等效模型,对多薄层组合材料在脉冲X射线辐照下的汽化反冲冲量和热击波进行了数值模拟研究。本文的主要研究成果及结论如下:1、对TC材料和GC材料的准静态压缩性能进行了实验研究,测量出了两种材料的弹性模量、泊松比和屈服强度,获得了两种材料的剪切模量分别为4.69MPa、3.29MPa。采用差示扫描量热法测量得到了TC材料和GC材料的DSC曲线,并由此得到了两种材料的比热在化学稳定状态随温度的变化规律。采用差热分析法测量得到了TC材料和GC材料的TG和DTA曲线。2、针对传统的压阻法测量系统的不足,建立了一种对称电桥测试系统。该系统电路简洁,能够方便地消除实验测量中的干扰信号,并可将冲击波压力测量范围延伸至0.2GPa左右,对于低阻抗材料在低压下的实验测量有重要价值。采用该方法在轻气炮上对TC材料和GC材料的Hugoniot参数进行了实验测量,结果分别为:C0TC=0.34 km/s,λTC=2.72;C0GC=1.23 km/s,λGC=3.02。给出了TC材料和GC材料的常态Grüneisen系数值及Grüneisen系数随比容的变化关系。3、针对脉冲X射线热击波在多薄层组合材料中可能出现的各种问题和困难,分析了采用等效模型的优越性。建立了多薄层组合材料系统的等效模型,获得了等效材料的物态方程参数。分别采用等效模型和分层模型对铝、铜和TC、GC多薄层组合材料在平面碰撞下应力波的传播进行了数值模拟检验,结果表明:在冲击载荷作用下的动态响应研究中,等效材料模型对于多薄层组合材料是适用的。4、通过物理分析,并结合数值计算中的具体情况,提出了采用压力对时间的积分来计算X射线辐照所产生的汽化反冲冲量的数值计算方法。分析表明,采用这种方法计算冲量更准确、更符合实际。5、对由TC材料和GC材料组成的多薄层组合材料在脉冲X射线辐照下汽化反冲冲量和热击波传播进行了数值模拟,得到了汽化反冲冲量和冲量耦合系数随初始能通量的变化规律和热击波传播规律。更多还原

【Abstract】 In order to study the thermodynamic response of the new multi-thin-layer structure materials irradiation by pulsed X-ray, the quasi-static, dynamic mechanical and thermal physical properties of TC and GC materials are measured by experiment, then established the equivalent model of the multi-thin-layer structure materials, and studied the blow-off impulse and thermal shock wave of multi-thin-layer structure materials irradiation by pulsed X-ray through numerical simulation.The main achievements and conclusions in this dissertation are presented in the following:1. The quasi-static compressive experiments of TC and GFSC materials are conducted, the mechanical parameters of two materials, such as poisson’s ratio, elastic modulus, yield strength are measured, and shear modulus of two materials can be gained as 4.69 and 3.29MPa. The DSC curves and the relation of specific heat versus temperature is obtained through differential scanning calorimetry, the TG and DTA curves are obtained through differential thermal analysis.2. In view of the characteristic and shortage of traditional piezoresistive measurement, a symmetrical electricity-bridge measurement system is established. The system is very simply, it can extend the range of pressure measurement to 0.2GPa, and can eliminate the interfere signals in the experiment signals better, which is very useful in low perssure measurement for low impedance materials. By ways of this method, the Hugoniot parameters of TC and GC are measured in the light-gas gun, the results is:C0TC=0.34km/s ,λTC=2.72 ; C0GC=1.23km/s ,λGC=3.02. and normal Grüneisen coefficients of TC and GC materials and the rule of coefficients as a function of ratio-volume are gained.3. In view of the problem and difficult of simulating the pulsed X-ray thermal shock wave in multi-thin-layer structure materials, analyze the advantage of adopting the equivalent model. Establish the equivalent model of multi-thin-layer structure materials, confirm calculate method of each parameter such as C0、λ、a andγ0 in the equivalent model. The equivalent model and delamination model are adopted to simulate the shock wave propagation in Al-Cu and TC-GC MTLSM under plane collision respectively. The result indicate: equivalent model is suit to research the dynamic response of multi-thin-layer structure materials under impact loaded.4. Through physical analysis, combined with the specific circumstances in numerical calculation,∑pg(t)Δt method to calculate the blow-off impulse generated by X-ray radiation is brought out. Analysis indicated: this calculate method is more accurate and realistic.5. Through calculating the blow-off impulse and simulating the thermal shock wave propagation induced by x-ray irradiating in TC-GC multi-thin-layer structure materials, the change rule of the blow-off impulse and the propagation rule of the thermal shock wave is gained.更多还原