Formation of voids in the Cr coatings with (110)-preferred orientation prepared by arc ion plating under an Au+ irradiation of 20 dpa

This paper presents the formation of voids produced by Au+ ion irradiation in the Cr coatings prepared by arc ion plating. Specially, the (110)-oriented crystallinity of the prepared coatings was characterized with XRD and selected for the first time as a variable for studying the size and number of voids. According to the tests of TEM, the void size is decreased and the void number is increased with increasing the (110)-oriented crystallinity. And the depth profiles of voids are also different in the coatings. Due to the voids resisting dislocation motion, the radiation hardening and disordering prevail on the coatings with low (110)-oriented crystallinities but are not found on the one with a high (110)-oriented crystallinities, which should be attributed to the small size of voids. Furthermore, big defect clusters provide high activation barriers for the survival of big voids. In addition, a softening is found on the well-arranged lattice due to the able-to-slip property of (110) planes for irradiated defects. •A competitive relationship between the void size and number are shown in the irradiated coatings under a damage of 20 dpa.•The activation barrier caused by defect clusters is employed to explain the survival of big voids.•Small voids cause a softening on the high (110)-oriented coating due to the able-to-slip property of (110) planes.