在高相对湿度下对环氧复合保温材料的降解和寿命预测
Jielin Ma1, Yan Yang1, Qi Wang1
1SP Group-NTU Joint Laboratory, School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
Polymers
|June 28, 2023
概括
交换机中的复合环氧绝缘故障是由热量和湿度引起的. 这项研究预测在正常条件下材料寿命为33.16年,确定水解是降解机制.
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:
- 分配开关设备的绝缘故障,特别是复合环氧材料,是部件损坏的重要原因.
- 高温和高湿度加快了这些关键隔热系统的退化.
研究的目的:
- 为了研究双A (DGEBA) /无水化物/瓦拉斯托尼特复合保温材料的二甲基乙烯的老化行为.
- 建立故障标准并预测这些材料在特定环境压力下的使用寿命.
主要方法:
- 复合环氧绝缘材料是使用造和固化技术准备的.
- 加速衰老实验是在75°C/95%RH,85°C/95%RH和95°C/95%RH进行的.
- 分析了材料,机械,热,化学和微结构性质,拉伸强度和红外碳结合吸收被用作故障指标.
主要成果:
- 拉力强度降低了50%,在材料故障点上,基碳结合的吸收率降低到大约28%.
- 一个寿命预测模型估计该材料在25°C和95%RH的使用寿命为33.16年.
- 降解归因于环氧键的水解,形成与填充剂离子反应的有机酸,损害了树脂-填充剂接口.
结论:
- 环氧树脂埃斯特键的水解是热和湿度压力组合下的主要降解机制.
- 有机酸和填充离子之间的反应导致接口破坏,增加表面的水友性和降低机械强度.
- 开发的寿命预测模型为评估交换机中复合环氧绝缘材料的耐用性提供了宝贵的见解.
相关概念视频
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01:24Carbonation Shrinkage
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01:20Microcracking in Concrete
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01:10Moisture Content and Bulking of Aggregate
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