周期性扰动促进了产量压力材料的超热爬行
Ezequiel E Ferrero1, Eduardo A Jagla2
1Instituto de Nanociencia y Nanotecnología, CNEA-CONICET, Centro Atómico Bariloche, (R8402AGP) San Carlos de Bariloche, Río Negro, Argentina. ezequiel.ferrero@conicet.gov.ar.
Soft matter
|July 25, 2025
概括
循环应力变化可以导致材料的不可逆转变形,即使在临界屈服应力以下. 确定了一个新的临界应力,西格玛-0,在此下变形停止,类似于疲劳极限.
科学领域:
- 物理 物理学 物理
- 地质物理学 地质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 产应力材料只有当应力超过临界值 (sigma-c) 时才会变形.
- 亚临界条件 (压力
研究的目的:
- 描述材料在循环参数变化引起的亚临界无热条件下不可逆转的变形.
- 调查新型临界压力 (sigma-0) 在这种现象中的作用.
主要方法:
- 利用已建立的模型从产生和定义过渡物理学.
- 分析了变形行为,因为关键应力值是从上面和下面接近的.
主要成果:
- 随着sigma-c从下方接近,每个周期的变形增加.
- 变形在新的临界应力,sigma-0 (< sigma-c) 时减少并消失,当从上面接近时.
- 西格玛-0的功能与疲劳极限在损伤传播中的功能相似.
结论:
- 循环的环境或系统参数波动可以在低于其产量压力的材料中引发持续的不可逆转的变形.
- 研究结果表明,在理解环境周期影响的次临界地形演变和土壤爬行机制方面,有潜在的应用.
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