Nanostructures composed of carbon nanotubes (CNTs) show great diversity in geometrical morphology, leading to effective augmentability in their unique properties and practical technological applications. In the present study, for the first time, highly controllable mechanical properties of three-dimensional (3D) conical coiled CNTs (CCNTs) structure, which are assembled from straight CNTs in a form of nanocone, were reported, resourcing to molecular dynamics simulations. As a result of the conical morphology, tensile mechanical behaviors of conical CCNTs are dominated by van der Waals (vdW) forces and covalent forces. Tensile stiffness and the way of phase transformation are controlled by geometrical characteristics in vdW forces’ domination section. Stretchability - that is situated in section of covalent forces’ domination - can vastly range from 250 to 23000%, depending on radius of each coil. More interestingly, originating from the hollow conical geometry, conical CCNTs can be highly compressed, as well as show different behaviors between cyclic compression and tension. This work provides new insights into mechanics of carbon nanostructures, and indicates that conical CCNTs are good potential candidates for mechanical robust nanodevices.

由碳纳米管 (CNT) 组成的纳米结构在几何形态上表现出极大的多样性，从而在其独特的性能和实际技术应用方面具有有效的可扩展性。在本研究中，首次报道了高度可控的三维（3D）锥形卷曲碳纳米管（CCNT）结构的机械性能，该结构由纳米锥形式的直碳纳米管组装而成，可用于分子动力学模拟。由于锥形形态，锥形 CCNT 的拉伸力学行为受范德华 (vdW) 力和共价力支配。抗拉刚度和相变方式由 vdW 力支配部分的几何特征控制。拉伸性——位于共价力支配的部分——可以在 250% 到 23000% 的范围内变化，具体取决于每个线圈的半径。更有趣的是，源自空心锥形几何形状，锥形 CCNT 可以被高度压缩，并在循环压缩和拉伸之间表现出不同的行为。这项工作提供了对碳纳米结构力学的新见解，并表明锥形 CCNT 是机械坚固纳米器件的良好潜在候选者。