环境和粘合层厚度对复合材料粘接接头故障模式的影响
Kang Yang1,2, Huan Feng1,2, Pengyang Li1
1College of Aerospace Engineering, Shenyang Aerospace University, Shenyang, 110136, China.
Scientific reports
|October 1, 2024
概括
这项研究在各种条件下研究了结构粘合剂关节. 较厚的粘合层和环境暴露显著降低了关节强度,特定厚度显示环境敏感性较低.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 复合材料 复合材料 复合材料
背景情况:
- 结构粘合剂对于粘合复合材料,如prepreg和纤维织物至关重要.
- 了解各种环境条件下 (温度,湿度,液体暴露) 的粘合性能对于结构完整性至关重要.
- 粘合层厚度是影响关节强度和故障模式的关键参数.
研究的目的:
- 评估结构粘合剂接头的机械性能和故障机制.
- 评估粘合剂层厚度对干燥和湿条件下的关节强度的影响.
- 为了确定暴露在水和液压油中的粘接接头的液体灵敏度.
主要方法:
- 单 lap 接头是使用结构粘合剂,单向 prepreg 和纤维织物制造的.
- 机械测试是在室温干燥 (RTD) 和升温湿 (ETW) 条件下进行的.
- 扫描电子显微镜 (SEM) 分析了断裂表面,而有限元模拟则模拟了故障模式.
主要成果:
- 随着粘合层厚度的增加,关节强度下降,特别是在ETW状态下 (52%的减少).
- 1.0毫米和1.5毫米的粘合层在RTD和ETW环境之间表现出最小的强度变化.
- 在水和液压油中浸泡将剪切强度降低了39%以上,故障模式包括附着和粘合层故障.
结论:
- 粘合剂层厚度和环境条件显著影响复合材料接头的机械性能.
- 最佳的粘合剂厚度对于保持关节强度至关重要,特别是在苛刻的环境中.
- 液体暴露会损害关节的完整性,需要对复合结构进行仔细的材料选择和设计考虑.
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