A combined experimental and simulation study to examine lateral constraint effects on microcompression of single-slip oriented single crystals

A custom in situ scanning electron microscopy mechanical testing system has been used to study the compressive deformation behavior of single-slip oriented Rene N5 single-crystal Ni superalloy microcrystals. Two different compression platens were used to explore the effect of lateral stiffness on the resultant mechanical response, which approximated either a high-friction or effectively zero-friction case. The change in the lateral constraint of the test system had a demonstrable effect on many aspects or attributes of plastic flow: the yield stress and strain-hardening behavior, the intermittency of strain bursts, the spatial distribution of slip bands, and the development of internal crystal rotations. Finite-element modeling of the microcompression experiments using an anisotropic crystal plasticity framework provided insight regarding changes in the internal stress field and resultant activity of slip systems. The experimental findings are rationalized based on these simulation results.