WC-Co hard alloy roller rings, with a hardness of HRA92, are used for precision cold-rolled strip steel. When rolling extremely thin strips of 0.002mm, the surface roughness Ra is ≤0.08μm. Tungsten carbide and other hard alloy materials have extremely high hardness (80-90HSD) and excellent wear resistance, and are applied in the precision rolling of small wire rods and cold-rolled extremely thin strip steel (such as hand-torn steel under 0.01mm).