Corrosive agent for ultra-low carbon silicon steel and corrosion method

The invention provides a corrosive agent for ultra-low carbon silicon steel and a corrosion method, and belongs to the technical field of metallographic sample preparation, the corrosive agent for the ultra-low carbon silicon steel comprises a first corrosive agent and a second corrosive agent; the first corrosive agent comprises protonic acid and a solvent; the second corrosive agent is a copper sulfate solution. The corrosive agent for the ultra-low carbon silicon steel comprises a first corrosive agent taking protonic acid as an effective corrosion component and a second corrosive agent taking a copper sulfate solution as an effective corrosion component, and the first corrosive agent and the second corrosive agent are matched with each other, so that the corrosive agent has higher corrosion capacity, defects generated by the two corrosive agents in the corrosion process are eliminated, and the corrosion performance of the ultra-low carbon silicon steel is improved. And the technical problem that the metal