在砂基板上的环氧和聚尿素涂层的洞穴演变过程
Caisheng Huang1, Xiaolong He1, Jianmin Zhang1
1State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China.
Ultrasonics sonochemistry
|February 21, 2024
概括
添加一个环氧砂层显著提高了聚合物涂层对化侵蚀的抗性. 使用这种层的聚尿素涂层显示出对长时间冲击的优越耐用性,最大限度地降低了基板损坏.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物工程 聚合物工程
- 表面工程是什么?表面工程是什么?
背景情况:
- 聚合物涂层对于保护砂等基材免受环境退化至关重要.
- 在超声波化等条件下了解故障机制对于材料开发至关重要.
- 现有的涂层可能缺乏足够的抗压性,导致过早的故障.
研究的目的:
- 研究各种聚合物涂层结构在砂上的化侵蚀失效机制.
- 评估中间环氧砂层在提高涂层性能方面的作用.
- 为了比较环氧和聚尿素涂料的化阻力,有和没有中间层.
主要方法:
- 准备了三种不同的聚合物涂层结构:环氧 (MEP1),环氧与中间环氧砂 (MEP2) 和聚氨酸与中间环氧砂 (MPU).
- 进行了超声波化实验,以模拟侵蚀条件.
- 损坏的表面的特征是为了分析洞穴分布和演变.
主要成果:
- 中间环氧砂层通过增强能量吸收和延迟坑形成,显著提高了化阻力.
- 中间层的粘附性防止了基板侵蚀,即使表面涂层受损.
- 聚尿素涂层 (MPU) 呈现出极好的弹性-塑性变形,能够承受长时间的化冲击,并呈现最小的侵蚀.
结论:
- 加入中间环氧砂层是一种有效的策略,可以提高聚合物涂层的化阻力.
- 聚尿素涂层与中间环氧砂层相结合,提供了优越的耐用性和防空蚀侵蚀的保护.
- 这些发现为设计适用于苛刻应用的强大的聚合物涂层系统提供了宝贵的见解.
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