Evaluation of mechanical ductile damage in sheet metal based on low-field magnetic analysis

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:539

Article

Silva, David D. S.¹  Raimundo, Rafael A.^2,3  Alves, Daniel N. L.²  Andrade, Micael R.⁴  Torquato, Ramon A.⁵  Gomes, Rodinei M.²  Morales, Marco A.³  Oliveira, Danniel F.⁵ 

[1] Univ Fed Sao Carlos, Grad Program Mat Sci & Engn, BR-13565905 Sao Carlos, Brazil

[2] Univ Fed Paraiba, Grad Program Mech Engn, BR-58051900 Joao Pessoa, Paraiba, Brazil

[3] Univ Fed Rio Grande do Norte, Dept Theoret & Expt Phys, BR-59078970 Natal, RN, Brazil

[4] Univ Fed Paraiba, Dept Mech Engn, BR-58051900 Joao Pessoa, Paraiba, Brazil

[5] Univ Fed Paraiba, Grad Program Mat Sci & Engn, BR-58051900 Joao Pessoa, Paraiba, Brazil

关键词: Low-field magnetic analysis (LFMA);    Non-destructive testing (NDT);    Mechanical ductile damages;    Plastic strain;    Finite element methods (FEM);   

DOI  :  10.1016/j.jmmm.2021.168403

来源: Elsevier

【 摘 要 】

This study proposes the application of low-field magnetic analysis (LFMA) as an alternative non-destructive testing method based on magnetic flux density for the detection of mechanical ductile damage in sheet metal under uniaxial stress. Ductile damage is related to the development of micro-voids and pores due to large plastic strains. The samples were strained to different levels of strains up to 21% and studied with LFMA after unloading. Our approach is based on the assumption that as the plastic strain in steel increases, more damage is accumulated in the microstructure and therefore the magnetic properties are modified. Numerical simulation using finite element method, as well as experimental measurements such as tensile test, hardness, X-ray diffraction and electrical resistivity, were also applied to validate the proposed method in the detection of damage in tensile sample. It was found that the magnetic flux density indeed varies proportionally to the strain (72.3-63.4 mT (0-12.4% damage) for H = 243.2 Oe). These results demonstrate that the LFMA can be used to evaluate mechanical damages caused by plastic strain changes induced on steel. Furthermore, the LFMA presents accurate results for low magnetic fields with high sensitivity and reliability.

【 授权许可】

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