Stripping of Ni-P coating on Mg alloy substrate

A method using HF and HNO_3 to strip electroless Ni-P coating on Mg alloy substrate was proposed. The performance of stripping solution with different content of HF and HNO_3 and the influence of different content of HF and HNO_3 on stripping effect were tested respectively. The results prove that a quantity of F~- in stripping solution can protect the substrate from corrosion by forming protective film which mainly is MgF_2. When (w(HF)∶)w(HNO_3)∶w(H_2O) is 4∶3∶3, the stripping solution has best stripping effect. Because HF has severe toxicity, protective measures must be taken during operation.