부산대학교 도서관

A turbine matrix sleeve in accordance with the invention includes an inner cylindrical structure made up of a first material. The inner cylindrical structure may include multiple blades and multiple channels running between the blades along an outside diameter thereof. The inner cylindrical structure further includes threads, such as right-hand or left-hand threads, on an outer surface thereof. An outer layer, made up of a second material different from the first material, is integrally bonded to the threads. This outer layer may be optionally embedded with hardened inserts or buttons, such as PDC inserts, diamond inserts, TSP inserts, or the like. The threaded surface on the inner cylindrical structure significantly improves the bond between the outer layer and the inner cylindrical structure and creates a mechanical lock therebetween.