3D打印CFRP-Ⅰ型层间断裂韧性的断层替换测试法及参数化分析  

Fracture layer replacement method and parameterized analysis of modeⅠinter-layer fracture toughness of 3D printing CFRP

作　　者：陈鹏宇 杨冰晨 药天运 许方舟 赵煜[1] 周勇军[1] CHEN Pengyu;YANG Bingchen;YAO Tianyun;XU Fangzhou;ZHAO Yu;ZHOU Yongjun(School of Highway,Chang′an University,Xi′an 710064,China;School of Civil Engineering,Chang′an University,Xi′an 710061,China)

机构地区：[1]长安大学公路学院,西安710064 [2]长安大学建筑工程学院,西安710061

出　　处：《哈尔滨工业大学学报》2024年第11期88-101,共14页Journal of Harbin Institute of Technology

基　　金：国家重点研发计划(2021YFB1600302);长安大学中央高校基本科研业务费专项资金(300102282108);陕西省自然科学基金(2022JM-275)。

摘　　要：为实现3D打印碳纤维增强树脂基复合材料(carbon fiber reinforced polymer,CFRP)Ⅰ型层间断裂韧性的测试分析,并量化评价打印参数对该型断裂韧性的影响规律,推进3D打印CFRP技术在桥梁工程中的应用,分别从试验及仿真角度开展了相关探索。首先,提出了一种新型的3D打印CFRP层间预制裂纹制备方法-断层替换法,利用该方法开展了系统性的试验研究,分析了两类关键打印参数对Ⅰ型层间断裂韧性的影响规律。其次,基于内聚区理论及surface-based cohesive关系,构建了各类打印工况下的预制裂纹试件双悬臂梁(double cantilever beam,DCB)试验的仿真模型,并完成了仿真计算与试验测试的对比分析。结果表明:3D打印CFRP的Ⅰ型层间断裂韧性随着打印温度及速度的提高而增大,且打印温度对断裂韧性的影响更显著,当温度由245℃升至285℃时,断裂韧性提高了294.6%;当速度由20 mm/s增至60 mm/s时,断裂韧性提高了27.6%;当打印温度与速度提高时,试件在打印过程中热量散失更小,Ⅰ型层间力学性能得到提高;但当打印速度过大时,印材在打印过程中无法完全沉积并实现较好的黏结,反而对Ⅰ型层间力学性能造成负面影响。同时,仿真结果与试验数据的相对误差均控制在15%以内,表明提出的断层替换法在I型层间断裂韧性试验数据获取方面是合理且稳定的。因此,该方法可为后续量化评价3D打印CFRP桥梁工程构件的层间力学性能提供试验技术支撑。In order to test and analyze the mode I inter-layer fracture toughness of 3D printing carbon fiber reinforced polymer(CFRP),and quantitatively evaluate the influence of printing parameters on the mode I fracture toughness,then promote the application of 3D printing CFRP technology in bridge engineering,experimental and simulation methods were used to carry out the relevant explorations,during this study.Firstly,a novel method for preparing inter-layer pre-cracks of 3D printing CFRP was proposed,namely fracture layer replacement method.Systematic experimental research was conducted by this method,and the influence of two types of key printing parameters on the mode I inter-layer fracture toughness was analyzed.Secondly,based on the cohesive zone theory and the surface-based cohesive relationship,simulation models of the double cantilever beam(DCB)test specimens with pre-cracks under various printing conditions were established.Meanwhile,a comparative analysis between simulation and experiment was carried out.The results indicate that the mode I inter-layer fracture toughness of 3D printing CFRP increases with the increase of printing temperature and printing speed,and the effect of printing temperature is more significant.When the temperature increases from 245℃to 285℃,the fracture toughness increases by 294.6%.When the printing speed increases from 20 mm/s to 60 mm/s,the fracture toughness increases by 27.6%.When the printing temperature and speed are increased,the heat loss of specimen in the printing process is smaller,and the mode I inter-layer mechanical properties are improved.However,excessive printing speed can hinder complete deposition and optimal bonding,resulting in negative effects on the mode I inter-layer mechanical properties.Moreover,the relative errors between simulation results and experimental data are controlled within 15%,which indicates that the fracture replacement method proposed in this study is reasonable and stable in terms of obtaining test data of type I inter-layer fracture tough

关 键 词：桥梁工程 3D打印CFRP Ⅰ型层间断裂韧性 断层替换法 内聚区理论 

分 类 号：TB332[一般工业技术—材料科学与工程]