Reference and DDQ-BH carburized grade having a lower reactivity were submitted to a galvannealing treatment at 480 °C for 20 s and 30 s respectivelly. The adherence of the alloyed coating was evaluated by cup test measurements. For equivalent Fe content (9.5 %) and coating weight (35 g/m²), the coating of both steel grades has an excellent adherence as shown by their low average powdering level of 22 mg/cup (table 3).