TREATMENT OF SURFACE OF GALVANIZED STEEL MATERIAL TO BE FRICTIONALLY JOINED

摘要

PURPOSE:To simply remove a zinc layer from the surface of a galvanized steel material to be frictionally joined by placing a coarsely knitted or punched sheet on the surface of the steel material and rubbing high viscosity paste contg. dil. hydrochloric acid on the surface of the steel material through the sheet. CONSTITUTION:A coarsely knitted or punched sheet is placed on the surface of a galvanized steel material to be frictionally joined. High viscosity paste contg. dil. hydrochloric acid is rubbed on the surface of the steel material through the sheet with a pallet, a roller or the like. When the steel material is allowed to stand for 1-2hr, a surface having the desired coefft. of friction is obtd. by the progress of a chemical reaction. The sheet, the paste and zinc chloride remaining on the surface are removed.