Tungsten was selected as the armor materials for divertor in ITER and candidate for the first wall in DEMO-like reactors.Ion-irradiations were carried out to research the particles interaction with target materials.However,the defects induced by ion-irradiation were distributed inhomogeneously in materials,owing to not only the damage profile but surface image force and defects diffusion at different temperatures.Such inhomogeneous distribution gives a warning to the researchers who correlate the irradiation hardening with the microstructure via nano-indentation measurement by loading in the direction parallel to the irradiation direction.