We present new results for the properties of phases and phase transitions in
spin-triplet ferromagnetic superconductors. The superconductivity of the mixed
phase of coexistence of ferromagnetism and unconventional superconductivity is
triggered by the presence of spontaneous magnetization. The mixed phase is
stable but the other superconducting phases that usually exist in
unconventional superconductors are either unstable or for particular values of
the parameters of the theory some of them are metastable at relatively low
temperatures in a quite narrow domain of the phase diagram. Phase transitions
from the normal phase to the phase of coexistence is of first order while the
phase transition from the ferromagnetic phase to the coexistence phase can be
either of first or second order depending on the concrete substance. Cooper
pair and crystal anisotropies determine a more precise outline of the phase
diagram shape and reduce the degeneration of ground states of the system but
they do not change drastically phase stability domains and thermodynamic
properties of the respective phases. The results are discussed in view of
application to metallic ferromagnets as UGe2, ZrZn2, URhGe.Comment: 21 pages, 7 figures; Phys. Rev. B (2005) in pres