A turbine ring sector made of ceramic matrix composite material has a portion forming an annular base with an inner face for defining the inner face of a turbine ring when the ring sector is mounted on a ring support structure and an outer face from which there extends an attachment portion for attaching the ring sector to the ring support structure, the ring sector further including inter-sector faces, each for facing a neighboring ring sector when the ring sector is mounted on the ring support structure; wherein the inter-sector faces are coated in an environmental barrier that is doped with an electrically-conductive compound and that presents at least one slot.