Characterisation of the damaging micromechanisms in a pearlitic ductile cast iron and damage assessment by acoustic emission testing
Characterisation of the damaging micromechanisms in a pearlitic ductile cast iron and damage assessment by acoustic emission testing
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DOI：
10.1111/ffe.13214
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发表时间：
2020-03-02
影响因子：
3.7
通讯作者：
Iacoviello, Francesco
中科院分区：
文献类型：
--
作者：
D'Angela, Danilo;Ercolino, Marianna;Iacoviello, Francesco
通过扫描电子显微镜(SEM)分析和声发射(AE)测试，研究了珠光体(EN-GJS700-2)球墨铸铁(DCI)的损伤微观机制。在应变控制下对微拉伸试件进行了单调单轴拉伸试验。通过拉伸夹持器在现场条件下进行了扫描电子显微镜分析。识别了多种损伤微观机制，并描述了它们随力学响应的演变。传统的声发射特征被发现与弹性行为中的断裂损伤的开始具有定性的相关性。根据Shannon公式和Kullback-Leibler公式评估的失效效应的信息熵与持续损伤和早期失效有很好的相关性。最后提出了试探性的失效准则。这种评估方法在结构健康监测方面是很有前途的。
The damaging micromechanisms in a pearlitic (EN-GJS700-2) ductile cast iron (DCI) are investigated by means of scanning electron microscope (SEM) analysis and acoustic emission (AE) testing. Monotonic uniaxial tensile tests are performed on microtensile specimens under strain control. SEM analysis is applied under in situ conditions by means of a tensile holder. The multiple damaging micromechanisms are identified, and their evolution along with the mechanical response is characterised. The traditional AE features are found to be qualitatively correlated to the onset of the fracture damage over the elastic behaviour. The information entropy of the AEs evaluated according to both Shannon and Kullback-Leibler formulations is proven to be well correlated to the ongoing damage and the incipient failure. Tentative failure criteria are finally proposed. The assessment approach is found to be promising for structural health monitoring purposes.