PURPOSE: To allow the hot extrusion of a work while maintaining the dimensional tolerance thereof over a long period of time by constituting the conjugated die of a work contact part consisting of a powder sintered body of a specific compsn. and a die base part having tensile strength of specific value.

CONSTITUTION: The powder sintered body which constitutes the work contact part 11a of the conjugated die 11 consists of the powder sintered body essentially consisting of the compsn. contg. ≤0.5wt.% C, ≤20wt.% Si, ≤2.0wt.% Mn, 8.0 to 20.0wt.% Cr, 64.0 to 84.0wt.% Ni, 1.0 to 7.0wt.% Mo, 1.0 to 5.0wt.% W, 3.0 to 10.0wt.% Al, 0.5 to 2.0wt.% Ti, and the balance Fe and unavoidable impurities. The die base part 11b fixed integrally by diffused junction to the work contact part is the steel kind having 60 to 100kg/mm2 tensile strength at 200 to 600°C. The generation of thermal deformation and wear at the time of extrusion working and the bulking, etc., of the base part is obviated in this way and the dimensional tolerance is maintained over a long period of time.