Anisotropic crystal plasticity model based on dislocation density is employed to investigate the mechanical response of nickel single crystalline micropillar, and is further verified by comparing its predictions with existing experimental data. Following that, we study nickel single crystalline micropillar with orientation having ［123］, and investigate the influence of common experimental errors of crystal orientations, friction, misalignment and taper angle, on the mechanical testing results. It is found that for the single-slip orientated micropillar, slight variation of crystal orientation leads to a transition from single-slip behavior to multi-slip deformation. Friction-affected lateral constraint shows a dramatic effect on the microcrystal strain hardening behavior. Small misalignments give rise to a decrease of elastic modulus, and change the prime slip direction in significant ways. The taper micropillar shows much smaller yield stress than no taper pillars do.
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