| Coating treatment of metal surface has been an important way of material surface modification, along with new requirement of energy-saving, environment protect and production cost, the processing method that firstly nickel was electrodeposited on the substrate and then metal plating material are plastic formed precisely has gradually formed. Recently, finite element method (FEM) has been an important method to study sheet metal forming, this method can not only forecast the distributions of stress-strain fields, discover the forming drawbacks and analyze the reason of forming drawbacks, but also it can analyze precisely the process parameter's impact to the forming process.In this thesis, the synthetical review on the present situation of sheet metal forming was firstly presented. Then some attention problems during simulation of coating material were investigated. Finally, the forming process of electrodeposited nickel coating was simulatly studied by ANSYS/LS-DYNA. The effects of process and module parameters were studied during the forming process. Some simulation results were validated by experiments. The main contents and results contain the following:(1) Through simulating the cup-stamping of electrodeposited nickel coating, the stress-strain fields, thickness variations of nickel coating and steel substrate were obtained. The force-displacement curves were also obtained. The results of the simulation illustrated that the stress-strain fields of the coating and substrate were maximum at die fillet. It was found that the stress field of the coating was more complicated than that of the steel sheet, which showed that the stress-strain distributed non-homogeneously at the bottom of cylindrical cup. Meanwhile, it was found the punch-nose radius was the most unsubstantial part for the intensity of the entire deep-drawing part and the thinnest part. It was the danger zone for the break and at this zone. The thickness thinning-rate of the steel sheet and the nickel coating were up to 4.8% and 6.7% respectively. The punch force increase first and decrease afterwards, when the depth of stamping was 12.62571mm and the punch force reached maximum 15.41846KN.(2) In order to validate the results of simulation, the cup-stamping of electrodeposited nickel coating was done by experiment. The results showed that the shapes of cylindrical cup were obtained by FEM and experiment results were agreed. The depth of cylindrical cup by FEM was 15.6mm and the depth of cylindrical cup by experiment was 16mm. At last, the interface combination status of the coating was observed by scanning electron microscopy (SEM). The thickness of the coating was measured by the measurement software of SEM, which showed the interfacial delamination would not happen and the thickness variation tendency of coating was similar to the simulation results.(3) The influences of blankholder force (BHF) on the forming quality of the electrodeposited nickel coating were studied. It was found that the sheets would wrinkle without BHF. When BHF (400N, 800N) was too small, the sheets would wrinkle during later stage. When BHF was 1KN, the quality of stamping parts was better. In order to improve the formability of the sheet, a curve of variable BHF (VBHF) was designed by us. The results illustrated that the VBHF could not only prevent wrinkle, but also it could prevent crack.(4) The influences of process parameters such as friction coefficient, the radius of die and the velocity of punch were studied during stamping process of the electrodeposited nickel coating by FEM. The results showed that higher friction coefficient would increase the punch force, the thickness of the substrate and coating at thinnest parts would thinner and the thinning-rate of the coating was higher than that of the substrate. Meanwhile, it was found that decrease of the radius of die and the raise of punch velocity would increase the tendency of crack.Through the research work, the forming characteristics of electrodeposited nickel coating and the influences of process parameters on the forming process were obtained. The results may serve as a reference for the stamping process of electrodeposited nickel coating in industrial fields.
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