PURPOSE: To improve the wear resistance and durability of the surface of a developer carrier and to obtain a sharp image by forming an Ni-Al alloy layer 1 on the surface of the developer carrier.

CONSTITUTION: The Ni-Al alloy layer 1a is formed on the surface of the sleeve 1 by plasma thermal spraying. In this case, Ni-2W7wt% Al alloy containing 2W7wt% aluminum based on the total weight causes exothermic reaction named as thermit reaction, so the adhesive strength among Ni-Al alloy particles and adhesion to the sleeve surface increase, so that a high-hardness thermally sprayed layer is formed. Further, the Ni-Al alloy has low porosity and is hard to separate from the sleeve surface and tolerant to wear. Further, the sleeve surface is normally roughened for the triboelectric charge donation due to abrasion against toner, improvement of toner conveyance, prevention against the fusion of toner on the sleeve, etc., but the discharge amount of powder during the plasma thermal spraying and a current value are increased to reduce the surface roughness, thereby giving desired roughness to the sleeve surface without any roughening work.