An adjustment ring (50) is configured to facilitate vane (30) position adjustment in a variable turbine geometry turbocharger (1), and is formed of an assembly of one or more first ring portions (60) that are formed of a first material, and one or more second ring portions (61) that are formed of a second material. The first material has different material properties than the second material. In some embodiments, high-wear portions of the adjustment ring (50) can selectively and cost-effectively be formed of wear-resistant material while remaining portions are formed of a conventional material. A cost-effective method of manufacturing multi-piece adjustment rings (50) is described.