Abstract: One technological problem about the weak combination of interface between Cr plating layer and substrate which was strengthened by plasma had been put forward according to the application state of under serious ablation and erosion by hot chemical airflow.The technology using distransfer plasma to heat the steel workpiece with Cr plating layer at high speed was used to strengthen interface bonding between Cr plating layer and substrate.The principle of strengthening with plasma was introduced in this paper and the process experiment of strengthening with plasma arc was carried out.The experimental results measurement and analysis show that the metallurgical bonding has occurred between Cr plating layer and substrate and the strengthening of interface bonding between Cr plating layer and substrate is improved remarkablely.