The structures of tungsten and tungsten carbide scaffolds play a key role in determining the properties of their infiltrated composites for multifunctional applications. However, it is challenging to construct and control the architectures by means of self-assembly in W/WC systems because of their large densities. Here we present the development of unidirectionally porous architectures, with high porosities exceeding 65 vol.%, for W and WC scaffolds which in many respects reproduce the design motif of natural wood using a direct ice-templating technique. This was achieved by adjusting the viscosities of suspensions to retard sedimentation during freezing. The processing, structural characteristics and mechanical properties of the resulting scaffolds were investigated with the correlations between them explored. Quantitative relationships were established to describe their strengths based on the mechanics of cellular solids by taking into account both inter- and intra-lamellar pores. The fracture mechanisms were also identified, especially in light of the porosity. This study extends the effectiveness of the ice-templating technique for systems with large densities or particle sizes. It further provides preforms for developing new nature-inspired multifunctional materials, as represented by W/WC-Cu composites.

钨和碳化钨支架的结构在确定其用于多功能应用的渗透复合材料的性能方面起着关键作用。但是，由于W / WC系统的密度大，通过自组装来构造和控制体系结构具有挑战性。在此，我们介绍了W和WC脚手架的单孔结构，其高孔隙率超过65％（体积），这些方面在许多方面都使用直接的冰模板技术再现了天然木材的设计图案。这是通过调节悬浮液的粘度以延迟冷冻过程中的沉降来实现的。研究了所得支架的加工，结构特征和机械性能，并探讨了它们之间的相关性。建立了定量关系，以通过考虑层间和层内孔，基于细胞固体的力学来描述其强度。还确定了断裂机理，尤其是根据孔隙率。这项研究扩展了冰模板技术对大密度或大颗粒系统的有效性。它进一步提供了预成型坯，用于开发新型的受自然启发的多功能材料，以W / WC-Cu复合材料为代表。