非线性静止波用于评估薄样品中的材料非线性
Seungo Baek1, Gun Kim1, Jin-Yeon Kim2
1Department of Civil, Urban, Earth, and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulju-gun, Ulsan 44919, Republic of Korea.
Ultrasonics
|June 27, 2024
概括
使用非线性静止波进行新的声学非线性参数 (β) 测量,可以准确地评估薄样品中的物质损伤. 这种先进的第二波生成技术克服了建筑材料以前方法的局限性.
科学领域:
- 材料科学 材料科学 材料科学
- 非破坏性测试是指非破坏性测试.
- 声学非线性 声学非线性
背景情况:
- 声学非线性参数 (β) 使用第二波生成 (SHG) 量化材料非线性.
- 目前用于测量建筑材料中的β的SHG方法受到样本大小的限制,导致边界反射阻碍了准确的评估.
- 大型样本要求限制了SHG与其他材料表征技术的整合.
研究的目的:
- 开发一种新的SHG方法,用于精确测量薄材料样本中的β.
- 克服与样本大小和边界反射有关的现有SHG技术的局限性.
- 为了使SHG与其他表征方式一起用于全面的材料分析.
主要方法:
- 开发了一种新的SHG方法,利用非线性静止波在没有强迫的配置中.
- 对反射波的相延迟和减弱效应进行了校正.
- 该方法允许在薄样本中进行准确的β测量,而无厚度-波长比限制.
主要成果:
- 拟议的SHG方法成功测量了在薄样本中的声学非线性参数 (β).
- 由于热损伤而导致的水泥中的微观结构变化,使用测量的β.量化.
- 该方法证明了其在受限制的样本大小中准确评估材料非线性的能力.
结论:
- 基于非线性静止波的新型SHG方法在薄样本中提供了准确的β测量.
- 这种技术克服了以前的局限性,使SHG能够在各种材料表征场景中应用.
- 该方法是量化材料微观结构变化的有希望的工具,例如热损伤.
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