Abstract

Negative work-hardening rates are precursors of plastic instabilities. The objective of the work is to determine the origin of the stress decrease in the case of prestrained sheet metals. Samples of low carbon steel and pure aluminium deformed in rolling and reloaded in simple shear exhibit softening for specific shear directions with respect to the rolling direction. Structural and textural evolutions are analysed with transmission electron microscopy and X-ray measurements, respectively. The low carbon steel shows clear evidence of intragranular structural destabilization while the Taylor factor, estimated by self-consistent calculations, remains nearly constant. It is deduced that for steel, the softening has a structural origin. By contrast the aluminium samples present identical structural changes whatever the sign of the work-hardening rate. It is shown that the latter is strongly correlated with Taylor factor evolutions. A textural instability is obtained in this case.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.