Abstract
Sputter-deposited high-purity copper specimens with grain sizes from 8.4 to 0.056 μm were tested in tension to investigate the influence of grain size on yield strength for small grain sizes. The smallest grain size in the sputter-deposited copper was a factor of 40 smaller than the smallest grain size previously available for yield-strength–grain-size studies of high-purity copper. The 0.2% offset yield strengths varied from 73.4 MPa for the coarsest-grained copper to 481 MPa for the finest-grained copper. The hardening was related to grain- and twin-boundary spacings. The yield strength obeyed the Hall-Petch relation even for the finest grain size of 0.056 μm, giving σy=6.39+3.74(l̄)−1/2 MPa, where σy is the 0.2% offset yield strength and l̄ is the mean intercept length (mm) between boundaries. The data agreed with the Ashby model, σ∼ (ε/l̄)1/2, only at very low strains (ε<0.001) for the specimens with very fine grain sizes (l̄⩽0.077 μm).
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 callDisclaimer: 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.
