Brush Plating for Renovating the Piston of Wing Flap Motion Tube

Abstract

In order to solve the repairing problem of worn piston of wing flap motion tube, the technology of brush plating Ni–diamond composite coating on the surface of high strength steel 18Cr2Ni4WA has researched. A new repairing technology was proposed based on the failure analysis of worn piston of wing flap motion tube. Using this coating system of brushing, Ni–diamond composite coating, through reducing the electrode potential of cathode, the degree of cathode polarization would be increased and make the speed of forming nuclei faster than the speed of growth of crystal nucleus, so the adhesion between the coating and basis material was increased. When the thickness of repairing coating is up to 30 μm, the hardness of the coating achieves 780 (HV); the adhesive power was better, and the adhesion tests are as follows: coating not fall off; the bend test: coating not peel off; the cupping test: height of test is 5.1 mm; the wear resistance of the repairing coating and the basis material’s approach. Tests have shown that qualified brush electroplating layer for repairing worn piston can be got through this kind of process.