Twinning-induced large tensile strains in directionally-solidified Fe100-xGax oligocrystals

JOURNAL OF ALLOYS AND COMPOUNDS

卷:863

Article

Jones, Nicholas J.¹  Lambert, Paul K.¹  Amanuel, Yared²  Dukes, Jazalyn D.^3,4  Yoo, Jin-Hyeong¹ 

[1] Naval Surface Warfare Ctr, Carderock Div, Phys Met & Fire Performance Branch, 9500 MacArthur Blvd, Bethesda, MD 20817 USA

[2] Naval Surface Warfare Ctr, Carderock Div, Maritime Syst Hydromech Branch, 9500 MacArthur Blvd, Bethesda, MD 20817 USA

[3] Naval Surface Warfare Ctr, Carderock Div, Criteria & Risk Assessment Branch, 9500 MacArthur Blvd, Bethesda, MD 20817 USA

[4] NIST, Engn Lab, Gaithersburg, MD 20899 USA

关键词: Twinning;    Digital image correlation (DIC);    Tension test;    Iron alloys;    Magnetostriction;   

DOI  :  10.1016/j.jallcom.2021.158738

来源: Elsevier

【 摘 要 】

Fe100-xGax alloys require highly textured samples for optimal magnetostrictive performance, which is often accomplished through directional solidification. In this study, we measure the mechanical properties of commercial Fe81.6Ga18.4 oligocrystals using sub-sized tensile specimens and digital image correlation (DIC). While many samples fractured around 360 MPa (the literature yield/tensile stress), most had discontinuous yielding as low as 186 MPa. Many of the samples also exhibited surprisingly large tensile strains, up to 5%, with substantial specimen-to-specimen variability. In all specimens, DIC showed high strain bands that develop at very defined angles, in agreement with electron back-scattered diffraction, which revealed significant deformation twinning. Published by Elsevier B.V.

【 授权许可】

Free