Abstract The magnetic properties of ion irradiated disordered Fe 60Co 40 thin films are studied by conversion electron Mössbauer spectrometry (CEMS). The evaporated films are ferromagnetic as the bulk alloy and exhibit a random spin orientation. It is shown that ion irradiation with 15 keV He ions does not change the magnetic properties. On the other hand, a 360 keV Xe ion irradiation produces a spin rotation resulting in their alignment parallel to the film plane. A correlation with the straining effect induced by the dense displacement cascades is proposed as a possible mechanism.