非晶合金因其长程无序、短程有序的独特原子结构呈现出高强度、高硬度、高弹性极限等一系列优异的力学、物理性能，引起人们的广泛关注。然而非晶合金在室温下表现为宏观脆性，极易导致材料发生灾难性失效，严重制约了它的工业发展前景。激光冲击强化作为一种工业化成熟的金属表面处理技术，在金属表面改性，改善材料疲劳、摩擦性能等方面的应用已十分广泛。本文主要探索了在激光冲击作用下非晶合金的响应特征及规律，研究了其微观结构及力学行为的演变规律与机制，为非晶合金强韧化研究提供新的思路。本文主要研究内容及结果如下：

    选取典型非晶合金为研究对象，对非晶合金激光冲击影响区响应特征进行研究。结果表明激光冲击能够导致在非晶合金内部会形成一个半椭圆形塑性影响区，不同体系非晶合金产生的塑性影响区深度不同。在影响区范围内存在大量弧形剪切带，研究剪切带沿深度方向的分布特征及规律，发现其与激光诱导冲击波传播特性密切相关。利用剪切转变区（STZ）模型，从能量角度解释了冲击波诱导非晶合金剪切带演化机制。

    对非晶合金内部塑性影响区力学性能进行研究。维氏硬度分析发现影响区中心位置沿深度方向硬度值表现为先下降，再回升，最终趋于稳定的变化趋势。残余压应力硬化与剪切带软化的相互竞争是硬度非线性波动的形成原因。进一步，通过纳米压痕矩阵研究了塑性影响区微观力学特性，结果表明影响区可以按照微观硬度演化划分为三个区域：（I）次表面软化区，（Ⅱ）中间硬度恢复区和（Ⅲ）基体硬度稳定区。利用赫兹理论研究了塑性影响区STZ激活体积的变化趋势，阐明了不同区域P-h曲线锯齿变化的诱因。通过分析激光冲击诱导的冲击波传播过程，从应力释放波的角度阐释了不同区域STZ激活体积变化的本质。

    研究了激光冲击非晶合金拉伸塑性的作用效果。铸态非晶合金样品的拉伸塑性为零，表现为典型的脆性断裂。激光冲击处理后，断裂模式发生改变，样品断裂角明显变小，Zr基和Ti基非晶合金的拉塑性得到提高。断口形貌分析获得了非晶合金由正应力主导断裂转变为剪应力主导断裂的直接证据。通过断裂过程分析解释了激光冲击改善非晶合金拉伸塑性的原因。

    对激光冲击处理后非晶合金动态力学行为进行研究。发现激光冲击后，非晶合金样品的储能模量在玻璃转变温度附近异常上升。透射电镜结果表明激光冲击能够导致非晶合金内部产生纳米尺寸局域有序结构，频率加载导致有序结构扩展，造成样品储能模量的上升。利用时温叠加法获得宽频域内非晶合金的动态力学行为，提出大量自由体积与局域有序结构共存机制是激光冲击样品不同加载频率下的异常动力学特性原因。通过Kohlrausch-Williams-Watts模型和准点缺陷理论研究了局域有序结构对非晶合金动力学行为的影响效果。

  The unique structure of metallic glasses (MGs) with long range disorder and short range order makes it exhibit some excellent mechanical, physical and chemical properties, such as high strength, high hardness and high elastic limit, which have attracted extensive attention. However, the macroscopic brittleness of MGs at room temperature can easily lead to catastrophic failure of materials, which seriously impedes its industrial application and development. Laser shock peening (LSP) is a maturely industrialized metal surface treatment technology. It has been widely used in modifying metal surface, improving material fatigue and friction properties. In this paper, we have studied the response characteristics of MGs under LSP, and then the evolution laws and mechanisms of microstructures and mechanical behavior are also researched. The main research items of this thesis are list as follows：

   The response characteristics of typical MGs after LSP are researched. The results show that a lot of round and arc-shaped shear bands with the size about dozens of micrometers are induced on the surface of MGs by LSP. While, a semi-elliptic plastic influence zone is found inside the MG. There are a lot of arc-shaped shear bands in the plastic influence zone. The distribution characteristics and rules of shear bands along the depth direction are studied, and it is found that it is closely related to the propagation characteristics of shock wave induced by LSP.

   The mechanical properties of plastic affect region inside MG induced  by LSP are studied. The analysis of Vickers hardness finds that the hardness values at the center of the region decrease first, then rise, and finally stabilize along the depth direction. A mechanism of interaction between compressive residual stress hardening and shear bands softening is proposed to explain the nonlinear fluctuation of hardness. Further, the micromechanical properties of the global deformation domain of the plastic affect region are studied by nano-indentation matrix. The results show that the region can be divided into three zones according to the evolution of microhardness: (I) softening region, (Ⅱ) hardness recovery region and (Ⅲ) hardness constant region. The variation trend of shear transformation zone (STZ) activation volume in different regions is studied by Hertz theory. The mechanism of STZ activation volume variation is explained from the perspective of stress release wave by analyzing the propagation process of shock wave induced by LSP.

    The effects of LSP on the tensile plasticity of MGs are studied. The tensile plasticity of as-cast MG sample is zero, which shows typical brittle fracture. The fracture mode has been changed and the fracture angle decreases obviously for samples treated by LSP. Both Zr-based and Ti-based MGs’ plasticities are improved. The fracture morphology analysis shows us the direct evidence of the transformation from normal stress dominant fracture to shear stress dominant fracture. The reasons for plastic improvement are explained by fracture process analysis

    The dynamic mechanical behavior of MG after LSP is researched. It is found that the storage modulus of MG increases abnormally near the glass transition temperature after LSP. The results of transmission electron microscopy show that LSP can induce the occurrence of local ordered precursors with nanometer size in MG, which can expand due to frequency loading and result in the abnormal increase in storage modulus finally. The dynamic mechanical behavior of MG in a wide frequency domain is obtained by the method of time-temperature superposition. The coexistence mechanism of a large number of free volumes and local ordered structures is proposed to explain the anomalous dynamic characteristics of LSP-treated samples under different loading frequencies. Kohlrausch-Williams-Watts model and quasi-point defects theory are adopted to analyze the effect of local ordered precursors on the dynamic behavior of MG.