摘要
碳纤维结构的破坏过程展示出韧脆性、突发性,失效机理呈现出多样性、复杂性,强度研究至关重要.鉴于近场动力学(peridynamics,PD)在材料断裂及损伤研究中的理论优势,本文提出一种新的复合材料近场动力学-杆单元(peridynamic-rod,PDROD)模型.其中,纤维束和树脂基体的力学行为分别由杆单元和PD模型表征,并建立了一种新的纤维/基体界面本构.与常规PD模型相比,PDROD存在两点优势:(1)数值模型能充分考虑各组分材料的物理特征,其便于调节纤维束的占比;(2)能精确捕捉到纤维和基体界面的脱黏模式.正因如此,该PDROD模型能应用于高性能复合材料的研发及损伤评估工作,其对于预浸料成型中纤维束占比调控及界面增韧性能评估具有重要作用.在数值分析中,详细探讨了纤维体积分数分别为10%,20%,40%和60%时复材的静态力学响应,结果显示PDROD模型能较好表征各向异性材料的力学属性.此外,通过开展拉伸载荷下单向板和层合板的失效问题研究,可以证实该计算模型在预测复材宏观损伤模式及失效机理等问题中的能力.
The failure process of carbon fiber-reinforced structures exhibits ductile-brittle and catastrophic characteristics,while the failure mechanisms demonstrate diversity and complexity,making strength research critically important.Leveraging the unique theoretical paradigm of peridynamics(PD),which offers a unified framework for modeling material degradation and fracture without pre-defined crack paths,this paper proposes a novel peridynamic-rod(PDROD)model to accurately predict the diverse and complex failure modes,such as delamination and matrix cracking,in composite materials.In this proposed model,the distinct mechanical responses of the fiber bundles and the resin matrix are respectively captured by rod elements and a peridynamic model,and a new interfacial constitutive law is specifically developed to govern the critical stress transfer and debonding behavior at the fiber/matrix interface.In comparison with the conventional PD model,the PDROD framework offers two primary advantages:(1)its numerical model can comprehensively account for the physical characteristics of each constituent material in the prepreg,facilitating easy adjustment of the fiber bundle proportion during the material design process;(2)it can accurately captures the debonding mode at the fiber/matrix interface due to the integration of a new cohesive zone model into the numerical framework.As a result,the PDROD model is particularly suitable for the development and damage evaluation of high-performance composites,and serves a critical function in controlling fiber volume fraction and characterizing interfacial toughening behavior during prepreg fabrication.In the numerical analysis,this paper systematically investigates the static mechanical response of the composite material at fiber volume fractions of 10%,20%,40%,and 60%.The results demonstrate that the PDROD model effectively characterizes the mechanical properties of anisotropic materials.Furthermore,through comprehensive investigations into the failure behavior of both unidirectional and multi-directional laminated composite structures under tensile loading conditions,the model's capability in predicting macroscopic damage patterns and identifying dominant failure mechanisms in composite structures has been validated.
作者
谭承锋
杨雄武
郑梦洁
茅东升
冯杰
Tan Chengfeng;Yang Xiongwu;Zheng Mengjie;Mao Dongsheng;Feng Jie(College of Materials Science and Engineering,Zhejiang University of Technology,Huzhou 313299,Zhejiang,China;State Key Laboratory of Advanced Marine Materials,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,Zhejiang,China)
出处
《力学学报》
北大核心
2025年第10期2410-2421,共12页
Chinese Journal of Theoretical and Applied Mechanics
基金
国家资助博士后研究人员计划(GZC20241796)资助.
