Dual-frequency ultrasonic cleaning with diluted phosphoric acid solution for removing oxide scale of uncoated steel sheets in hot stamping

Abstract Dual-frequency ultrasonic cleaning with a diluted phosphoric acid solution was developed to remove oxide scales on surfaces of hot-stamped parts from uncoated steel sheets, and conventional shot blasting processes are omitted. The removal the scale by is accelerated dual frequency. removing time for shorter than that hydrochloric solution, rust appearing leaving after prevented generating an iron phosphate layer. In dual-frequency dissolved, then were exfoliated thin high-pressure portions. decreased decreasing pH thickness increasing temperature. surface roughness distortion ultrasonic-cleaned part smaller those blasting, weldability paintability similar. having nonuniform distribution successfully removed solution.