Vector and tensor polarization parameters were measured for deuterons elastically scattered by 40Ca at 5, 7, 9 and 11 MeV. These data together with polarization data at 22 MeV and all available elastic scattering cross-section data from 5 to 34 MeV were analysed in terms of the optical model with vector spin-orbit coupling. A potential whose parameters change smoothly with energy describes the cross-section and vector polarization data reasonably well. Calculations performed at 9 and 22 MeV in which a tensor spin-orbit coupling was included gave somewhat better fits to the observed tensor polarizations than were obtained with a vector spin-orbit coupling alone. Some calculations on the 40Ca(d, p)41Ca reaction were also performed to test the usefulness of the deuteron potential found here as a distorting potential in distorted-wave theory. The calculations reproduce qualitatively the observed j-dependence in the stripping cross section. The predicted polarizations of outgoing protons show little similarity to the measurements. © 1969.