标题： 一种对刚性五模式的重新发现。 对“高体积模量五模式：三维金属水”的评论 显示英文标题

标题： A rediscovery of stiff pentmodes. A comment on "High bulk modulus pentamodes: the three-dimensional metal water"

摘要： 我们注意到Brambilla等人在[极端力学字母 74 (2025) 102267; arXiv:2406.14502]中声称发现了一种五模材料的新设计是不正确的。早在2016年，Briane、Harutyunyan和我[复杂系统数学与力学 5 (2016) 41--94; arXiv:1606.03305]设计了一类刚性五模材料，其中包括Brambilla等人所述的高体积模量五模材料。我们的设计推广到了三维，并且实现了完全各向异性，这是Sigmund在[力学与物理固体杂志 48 (2000) 397--428]中二维结构的主要方面。强调的是，Brambilla等人的深入分析远远超出了我们的简要处理。 显示英文摘要

摘要： We bring attention to the fact that the claim of Brambilla et.al. [Extreme Mechanics Letters 74 (2025) 102267; arXiv:2406.14502] of discovering a novel design for pentamode materials is incorrect. Back in 2016 Briane, Harutyunyan and myself [Mathematics and Mechanics of Complex Systems 5 (2016) 41--94; arXiv:1606.03305] designed a class of stiff pentamodes, that include the high bulk modulus pentamodes of Brambilla et.al. Our design generalized to three-dimensions, and to full anisotropy, the main aspects of a two-dimensional construction of Sigmund [Journal of the Mechanics and Physics of Solids 48 (2000) 397--428]. It is emphasized that the in depth analysis of Brambilla et.al. goes well beyond our brief treatment.