Compound membrane and formation manner null of plating and

摘要

PROBLEM TO BE SOLVED: To bond a plating film and a fluororesin and to form a film hard to be peeled by forming a plating film having innumerable cracks by electrolytic plating on the surface of a base metal, forming a fluororesin film on the surfaces of the cracks and executing baking in a vacuum furnace. ;SOLUTION: On the surface of a base metal 1 such as iron, aluminum, copper, their alloys or the like, a plating film 2 of chromium, nickel or the like is formed to a thickness of 1.5 to 30 μm by electrolytic plating, and, on the upper layer, a fluororesin film 4 of PFA, FEP, PTFE or the like is moreover formed to impart performance such as corrosion resistance or the like to the base metal 1. At this time, conditions such as voltage or the like in the electrolytic plating are controlled, innumerable cracks 3 are formed on the plating film 2, and, moreover, heating treatment such as baking or the like at about 300°C is executed to expand the cracks 3. After that, on the surfaces of the cracks 3, the fluororesin film 4 is formed by powder coating, fluidized dipping, spray coating, dip coating or the like, and, subsequently, it is baked at about 380°C in a vacuum to obtain the composite film securely infiltrated and hardened into the cracks 3.;COPYRIGHT: (C)2000,JPO