Very heavy doses of B ions, up to 22 At%, were implanted into Nb3Al substrates depleted of Al. Energies as high as 1 MeV were used. The surface composition was Nb3Al1−xBx where x varied from 0 to 1 over a distance of 20,000Å. Auger analysis was done to determine composition depth profiles. Structure was analyzed with a diffractometer using Cr radiation. The x-rays sampled primarily the implanted layer. Phase analysis was carried out as a function of incremental heat treatments up to 1000 C. The A–15 phase was always present although its composition was uncertain. The tetragonal Nb3B2 phase appeared after annealing at 95OC. Superconducting transition temperatures were measured at all stages; no increase in Tc above that of the substrate was observed.