[en] Swelling in nuclear materials is a serious materials problem in reactor development. Alloys have been found to be more resistant to swelling than pure metals. In order to investigate the effect of solute atoms on void formation, pure Nickel and its three binary alloys Ni-45 ppm c, Ni-124 ppm c and Ni-721 ppm c were irradiated 625 degree centigrade with a dose of 1 * 10/sup/16 Ni/sup/+ ions/cm square of 100 Kev energy. The effect of temperature in range 475-675 degree centigrade on swelling in nickel has also been studied. Preliminary results show that swelling reduces with increase in Carbon content and maximum swelling in Nickel occurs at 625 degree centigrade. These preliminary results are compared with the data obtained by Sorensen and Chen in neutron irradiated nickel. (author)