Magnetic characterization of cold rolled and aged AISI 304 stainless steel

• Published in: NDT & E international : independent nondestructive testing and evaluation 2005-12, Vol.38 (8), p.674-681
• Main Authors: Palit Sagar, S., Ravi Kumar, B., Dobmann, G., Bhattacharya, D.K.
• Format: Article
• Language: English
• Subjects: Analysing. Testing. Standards; Applied sciences; Barkhausen emission; Cold rolling; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Martensite; Materials science; Materials testing; Measurement of properties and materials state; Metals. Metallurgy; Nondestructive testing; Physics; Residual stress; Stainless steel; Texture; X-ray diffraction
• ISSN: 0963-8695; 1879-1174
• DOI: 10.1016/j.ndteint.2005.04.004

Magnetic easy axis predicted by the orientation distribution of the maximum amplitude of magnetic Barkhausen emission (MBE), which is obtained by magnetization in radial directions from the center of the specimens has been applied to determine the magnetic anisotropy on cold rolled and aged 304 SS in two sets of specimen. The maximum of the MBE has been found to orient along the rolling direction (RD) compared to the transverse direction (TD), indicating the presence of magnetic easy axis along the rolling direction for both sets. The strain induced martensite phase transformation has been determined using X-ray diffraction technique. The orientation distribution function (ODF) analysis has been carried out to obtain the crystallographic texture with cold rolling. ODF analysis revealed the 〈110〉 texture as the major. The magnetic anisotropy factor has also been determined with cold deformation and noticed that the strength of magnetic anisotropy decreases above 50% deformation for both the sets. Results have been explained considering two competitive effects, formation of crystallographic texture in the martensite phase and presence of compressive residual stresses along RD during cold rolling.