Turbine wheels, turbine engines, and methods of forming the turbine wheels are provided herein. In an embodiment, a turbine wheel includes a rotor disk and a plurality of turbine blades. Each turbine blade is operatively connected to the rotor disk through a blade mount, which is bonded to the rotor disk. The blade mount and the rotor disk have a fore surface on a higher pressure side thereof and an aft surface on a lower pressure side thereof. The blade mount includes a blade attachment surface that extends between and connects the fore surface and the aft surface. The turbine blade extends from the blade attachment surface. A gap is defined between adjacent blade mounts. The gap separates the blade mounts and extends into the rotor disk. The gap includes a pocket that has a fore opening in the fore surface. A pocket seal is disposed in the pocket.