Liu Xunchen, Wang Wenxuan, Zhao Yingchao, Wu Haibo, Chen Si, Wang Lanxin
School of Automotive Engineering, Wuhan University of Technology, Wuhan 430070, China.
Shandong Iron and Steel Group Rizhao Co., Ltd., Rizhao 276805, China.
Materials (Basel). 2025 Aug 30;18(17):4069. doi: 10.3390/ma18174069.
Inspired by natural gradient structures observed in biological systems such as lobster exoskeletons and bamboo, this study proposes a biomimetic strategy for developing advanced automotive materials that achieve an optimal balance between strength and ductility. Against this backdrop, the present work systematically reviews the design principles underlying natural gradient structures and examines the advantages and limitations of current additive manufacturing-specifically selective laser melting (AM-SLM)-as well as conventional forming and machining processes, in fabricating nature-inspired architectures. The research systematically explores hierarchical gradient designs which endow materials with superior mechanical properties, including enhanced strength, stiffness, and energy absorption capabilities. Two primary strengthening mechanisms-hetero-deformation-induced (HDI) hardening and precipitation hardening-were employed to overcome the conventional strength-ductility trade-off. Gradient-structured materials were fabricated using selective laser melting, and microstructural analyses demonstrated that controlled interface zones and tailored precipitation distribution critically influence property improvements. Based on these findings, an integrated material design strategy combining nature-inspired gradient architectures with post-processing treatments is presented, providing a versatile methodology to meet the specific performance requirements of automotive components. Overall, this work offers new insights for developing next-generation lightweight structural materials with exceptional ductility and damage tolerance and establishes a framework for translating bioinspired concepts into practical engineering solutions.
受龙虾外骨骼和竹子等生物系统中观察到的天然梯度结构的启发，本研究提出了一种仿生策略，用于开发在强度和延展性之间实现最佳平衡的先进汽车材料。在此背景下，本工作系统地回顾了天然梯度结构的设计原理，并研究了当前增材制造——特别是选择性激光熔化（AM-SLM）——以及传统成型和加工工艺在制造受自然启发的结构方面的优点和局限性。该研究系统地探索了赋予材料优异机械性能的分级梯度设计，包括增强的强度、刚度和能量吸收能力。采用了两种主要的强化机制——异质变形诱导（HDI）硬化和沉淀硬化——来克服传统的强度-延展性权衡。使用选择性激光熔化制造了梯度结构材料，微观结构分析表明，受控的界面区域和定制的沉淀分布对性能提升至关重要。基于这些发现，提出了一种将受自然启发的梯度结构与后处理相结合的综合材料设计策略，提供了一种通用方法来满足汽车零部件的特定性能要求。总体而言，这项工作为开发具有卓越延展性和损伤容限的下一代轻质结构材料提供了新的见解，并建立了一个将仿生概念转化为实际工程解决方案的框架。
