Cross Sections for (n,xp), (n,xd), and (n,xα) reactions induced by 15-MeV neutrons on 27Al, 46Ti, and 48Ti have been measured with a quadrupole spectrometer. Particles with energies as low as 800 keV were detected. Large sub-Coulomb-barrier peaks are found in the proton spectra from 27Al and 46Ti, but not from 48Ti; alpha-particle and deuteron spectra do not show such a peak. The presence or absence of such a peak is found to be related to the importance of the (n,n’p) reaction for a given isotope. Enhancement of the total proton-pro-duction cross section by almost a factor of 2 through such reactions is found for 27Al and 46Ti