Abstract
The effects of fibrous Cr phase on the adiabatic shearing anisotropic behavior of the Cu-15Cr in-situ composite model alloy were firstly studied by a split Hopkinson pressure bar (SHPB), Optical Microscope (OM), and X-ray diffraction (XRD) technique. Specimens were loaded along the rolling direction (Cu-15Cr0 degrees) and perpendicular to the rolling direction (Cu-15Cr-90 degrees). The experimental and analysis results showed that there were differences in the number of phase interfaces and phase interface distance that the shear stress crossed when sheared along with different directions due to the directional arrangement of the fibrous Cr phases, which caused the strain hardening, strain rate hardening and thermal softening of the Cu15Cr in-situ composite were anisotropic. The Cu-15Cr-90 degrees specimen possessed lower strain rate hardening and higher thermal softening at the same strain rate, and the strain hardening rate was similar to that of the Cu-15Cr-0 degrees specimen as the shearing process proceeded, so the Cu-15Cr-90 degrees specimen was more prone to adiabatic shearing than the Cu-15Cr-0 degrees specimen. In addition, a splitting crack was produced at the Cr phase and matrix interface in the Cu-15Cr-0 degrees specimen due to the additional tensile stress produced in the Cr phase during shearing. The perpendicular Cr phase in the Cu-15Cr-90 degrees specimen was deflected parallel to the shear stress during shearing, so it was not easy to produce splitting cracks. However, the tip of the Cr phase without deflection was more likely to possess high additional tensile stress, so the crack in the Cu15Cr-90 degrees specimen was extended along the edge of the adiabatic shear region at the tip of the Cr phase. (c) 2022 Elsevier B.V. All rights reserved.
NSTL
Elsevier