METHOD FOR COVERING IRON MEMBER WITH ZN-AL EUTECTOID ALLOY

摘要

PURPOSE:To develop composite material having high damping capacity and superior corrosion resistance, workability and adhesive property, by plating molten Zn-Al eutectoid alloy to surface of iron member, then cooling said member under a specified condition. CONSTITUTION:Surface of steel sheet is blasting treated, then degreased by aqueous NaOH soln., further neutralized by HCl and washed. Next, flux composed of ZnCl2 and NH4Cl is coated thereon by uniform thickness, said sheet is preheated to 450-550 deg.C, then passed through molten bath of Zn-Al eutectoicd alloy and molten plated. The plated layer is air cooled to temp. of boundary line between mixed phase of alpha phase + liquid phase and alpha phase in equilibrium diagram, then water cooled. Grain diameter of Zn-Al eutectoid alloy in plated layer is refined and iron member such as steel sheet covered with Zn-Al eutectoid alloy layer superior in adhesive property, workability, corrosion resistance is manufactured.