在考虑温度循环的多因素衰老试验下,高温化的加速恶化机制
Shiyin Zeng1, Wendong Li1, Yanan Peng1
1State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China.
Polymers
|August 12, 2023
概括
高温化 (HTV-SR) 的老化过程非常复杂. 这项研究表明,更广泛的温度循环范围加速HTV-SR降解,影响复合材料绝缘体性能.
科学领域:
- 材料科学 材料科学 材料科学
- 电气工程 电气工程
- 聚合物化学 聚合物化学
背景情况:
- 高温化 (HTV-SR) 对复合材料绝缘体至关重要.
- 热量,冠状病毒和湿度等环境压力加速HTV-SR的衰老.
- 复杂的衰老机制,特别是热循环,需要进行系统的研究.
研究的目的:
- 建立一个模拟HTV-SR.现场条件的多因素老化平台.
- 为了研究HTV-SR在温度循环,湿度和冠状泄漏的结合下老化的机制.
- 为了将老化程度与温度循环参数和材料性质变化相关联.
主要方法:
- 开发一个具有四个温度循环设置的多因素老化平台.
- 暴露HTV-SR样本于模拟的老化条件,每个周期为15个周期.
- 陈旧样品的全面表征,包括表面形态,疏水性,化学,机械和电气性质.
主要成果:
- 衰老程度与温度循环范围直接相关.
- 较大的温度差异 (70°C) 会导致高交叉连接,但易碎的材料容易破裂.
- 裂纹促进冠状体产物和水分的入,导致进一步的氧化和物质降解 (疏水性差,界面极化高).
结论:
- 温度循环通过改变交叉连接降解平衡,显著影响HTV-SR老化.
- 材料降解因联合压力而加剧,导致性能恶化.
- 了解这些衰老机制对于提高复合材料绝缘体的耐用性至关重要.
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