Method for conversion treating surface of magnesium alloy workpiece

摘要

A method for conversion treating a surface of a magnesium alloy workpiece includes the following steps: providing a magnesium alloy workpiece, degreasing the magnesium alloy workpiece, acid pickling the magnesium alloy workpiece in a first acid pickling treatment step, surface conditioning the magnesium alloy workpiece in a first surface conditioning treatment step, acid pickling the magnesium alloy workpiece in a second acid pickling treatment step, surface conditioning the magnesium alloy workpiece in a second surface conditioning treatment step, pre-phosphating the magnesium alloy workpiece in a pre-phosphating treatment step, and phosphating the magnesium alloy workpiece in a phosphating treatment step to form a phosphating film on the surface of the magnesium alloy workpiece.

主权项

1. A method for conversion treating surface of a magnesium alloy workpiece comprising:
providing a magnesium alloy workpiece; placing the magnesium alloy workpiece in a degreasing solution to remove oil from a surface thereof; placing the magnesium alloy workpiece in an acid pickling solution in a first acid pickling treatment step to remove oxides, release agent, dirt and magnesium granules left behind in cold working adhered on the surface thereof; placing the magnesium alloy workpiece in a surface conditioning solution in a first surface conditioning treatment step to remove residues adhered on the surface thereof after the first acid pickling treatment step; placing the magnesium alloy workpiece in the acid pickling solution in a second acid pickling treatment step to further remove oxides, release agent, dirt and magnesium granules left behind in cold working adhered on the surface thereof; placing the magnesium alloy workpiece in the surface conditioning solution in a second surface conditioning treatment step to remove residues adhered on the surface thereof after the second acid pickling treatment step; placing the magnesium alloy workpiece in a pre-phosphating solution in a pre-phosphating treatment step to neutralize a residual solution on the surface thereof after the second surface conditioning treatment step; placing the magnesium alloy workpiece in a phosphating solution in a phosphating treatment step to form a phosphating film on the surface thereof; wherein the phosphating solution comprises phosphoric acid, manganese phosphate acid, calcium dihydrogen phosphate, sodium zirconate, sodium vanadate, and sodium molybdate, and sodium silicate.