Wear resistant vibration assembly and method

A wear resistant vibration assembly 200 for transmitting a pressure pulse in a drill string. The assembly comprises a positive displacement power section disposed in an inner bore 224 of a housing 226, the power section including a rotor 214 disposed at least partially within a stator 216. The rotor is configured to rotate within the stator upon fluid flow through the power section. A lower thrust bearing 282 is disposed at the lower end of the rotor, wherein the lower thrust bearing includes a rotor bearing 294 disposed above and in contact with a second bearing 296. A valve is disposed above the power section within the inner bore of the housing and includes a rotating valve segment 204 disposed below a non-rotating valve segment 202 where each segment includes at least one fluid passage. The rotating valve segment is configured to rotate relative to the housing with a rotation of the rotor for cycling the valve between an open and restricted position, wherein in the open position the fluid passage of the rotating valve segment is aligned with the fluid passage of the non-rotating valve segment. In the restricted position the fluid passage of the rotating valve segment is at least partially unaligned with the fluid passage of the non-rotating valve segment for restricting the fluid flow through the valve to generate and transmit an unobstructed pressure pulse through the drill string above the valve.