CAJ | 학술논문

针对微脱黏测试建立细观力学模型，通过模拟纤维从树脂微滴中的拔出过程评价炭纤维增强双马树脂基复合材料的界面性能。为了深入理解湿热环境对复合材料界面性能的影响，通过微脱黏方法测试不同湿热环境条件下炭纤维增强双马树脂基复合材料的界面剪切强度。结果表明，湿热老化会导致界面剪切强度下降，吸湿达到饱和后界面剪切强度也会趋于稳定。在实验的基础上，基于内聚力界面单元建立脱黏过程的数值模型以表征复合材料的界面特性，评价实验参数与界面特性的关系。微脱黏模型还为宏观力学性能的数值分析提供包括界面相在内的必要的实验参数。微脱黏测试的有限元分析表明刮刀夹持位置、热残余应力以及湿热条件均会对界面应力分布产生影响。
침대미탈점측시건립세관역학모형，통과모의섬유종수지미적중적발출과정평개탄섬유증강쌍마수지기복합재료적계면성능。위료심입리해습열배경대복합재료계면성능적영향，통과미탈점방법측시불동습열배경조건하탄섬유증강쌍마수지기복합재료적계면전절강도。결과표명，습열노화회도치계면전절강도하강，흡습체도포화후계면전절강도야회추우은정。재실험적기출상，기우내취력계면단원건립탈점과정적수치모형이표정복합재료적계면특성，평개실험삼수여계면특성적관계。미탈점모형환위굉관역학성능적수치분석제공포괄계면상재내적필요적실험삼수。미탈점측시적유한원분석표명괄도협지위치、열잔여응력이급습열조건균회대계면응력분포산생영향。
Carbon fiber/bismaleimide composites have received increasing interest, owing to their excellent properties, especially their toughness under extreme working conditions. We established a micromechanical model for a finite element simulation of the micro-droplet test, which involves pulling a carbon fiber out of a bead of matrix using two moving knives acting on the bead as scrapers to quantify the interfacial properties of carbon fiber reinforced bismaleimide composites. The interfacial shear strength of carbon fiber/bismaleimide composites subjected to different hydrothermal environments was tested by micro-droplet method to illus-trate the impact of moisture absorption on their interfacial properties. Hydrothermal aging caused a reduction of interfacial shear strength, which leveled off when the immersion time in water exceeded 7 days at 71℃. A numerical simulation of the debonding process was performed based on the interface cohesive element damage model to simulate the interfacial properties of the composite and to determine the correlation between experimental parameters and interfacial properties. The simulation successfully provided es-sential parameters for numerical analysis of the macroscopic mechanical properties of the composite. Finite element analysis of the micro-droplet test revealed that the factors that influence the interfacial shear stress distribution are the position of the knives on the bead, thermal residual stress and hydrothermal treatment conditions.