METHOD FOR DECREASING SPRING BACK OF ALLOY SHEET BY PERFORMING SOLUTION TREATMENT PROCESS AND ADDITIONAL HEAT TREATMENT ON Al-Mg-Si ALLOY SHEET BEFORE PRESS FORMING

摘要

PURPOSE: To provide a method for minimizing spring back phenomenon after finishing forming by additionally heat treating the alloy sheet passing through the solution treatment process at a certain temperature for a certain time prior to the press process of forming an Al-Mg-Si alloy sheet in a product shape, thereby lowering yield strength of the alloy sheet. CONSTITUTION: The method for decreasing spring back of Al-Mg-Si alloy sheet is characterized in that the alloy sheet passing through the solution treatment process is heat treated at a temperature between 230 and 400 deg.C for 30 minutes to one hour prior to the press process of forming an Al-Mg-Si alloy sheet in a product shape.