Due to their excellent mechanical properties, nanoparticles have great potential as reinforcing phases in composite materials, friction modifiers in liquid lubricants, catalysts and drug-delivery agents. In the present study, the mechanical analysis of individual spherical hollow BN nanoparticles (BNNPs) using a combination of in situ compression tests inside a high-resolution transmission electron microscope (TEM) and theoretical modelling was conducted. It was found that BNNPs display high mechanical stiffness and a large value of elastic recovery. This enables the hollow BNNPs to exhibit considerably large cyclic deformation (up to 30% of the sphere's original external diameter) and to accumulate plastic deformation of approximately 30% of the total compression strain. Theoretical simulations allowed for elucidation of BNNPs’ structural changes under compression at the atomic level and explained the origin of their high stiffness and large critical deformation values.

中文翻译：

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中空BN纳米粒子的压缩特性：使用高分辨率透射电子显微镜的理论建模和测试

由于其优异的机械性能，纳米颗粒作为复合材料中的增强相，液体润滑剂中的摩擦改进剂，催化剂和药物传递剂具有巨大的潜力。在本研究中，使用原位结合对单个球形空心BN纳米颗粒（BNNPs）进行力学分析在高分辨率透射电子显微镜（TEM）内进行了压缩测试并进行了理论建模。发现BNNP显示出高的机械刚度和很大的弹性回复值。这使中空的BNNP表现出相当大的周期性变形（不超过球体原始外径的30％），并累积了约30％总压缩应变的塑性变形。理论模拟可以阐明BNNP在原子级压缩下的结构变化，并解释了其高刚度和较大的临界变形值的起源。