Pass Laws And Optimization On The Process Parameters In Multi-pass Single Point Incremental Forming

The metal sheet multi-pass single point incremental forming can manufacture straight wall parts that have large forming angle,and the complex parts owned fine forming quality can be manufactured by the process,which has not special dies and is suitable for research and development and personalized small batch production.The paper used the numerical simulation and tests to study on the multi-pass forming of straight wall cylinders and box parts with 1060 Aluminum sheet and researched laws of the forming pass,the effection laws of process parameters and the optimization on process parameters,and some practical researches were obtained,which provided some reference resources for the subsequent study on the multi-pass single point incremental forming.Firstly,the paper introduced the simulation software,research methods and test devices.Some simulation parameters including element model,material model,friction situation and forming path were described,and some test devices were represented such as test equipment,forming device,clamp and forming tool.Secondly,the pass calculation formula of multi-pass single point incremental forming was researched on straight wall cylinders and box parts with 1060 Aluminum sheet.The coefficient?m₁?of the first incremental forming was obtained on straight wall cylinders based on the traditional forming pass calculation about multi-pass punching technology,m₁=0.5,and the coefficient?m₁?of the first incremental forming was determined on box parts,m₁=0.333.The subsequent average forming coefficient?m?of multi-pass incremental forming was obtained about straight wall cylinders,m=1.212,and the subsequent average coefficient?m?of multi-pass incremental forming was gained on box parts,m=1.383,while the pass calculation formula of multi-pass incremental forming were determined respectively on straight wall cylinders and box parts.The formulas were verified through the numerical simulation technology and some parts were manufactured by test devices to verify the accuracy of numerical simulation.Finally,effection laws of some parameters were studied for the uniformity of sheet thickness,and those parameters would be optimized.The forming tool diameter and friction coefficient were positive relation with the uniformity of sheet thickness on parts fabricated,and the press amount and feed were inverse relation with the uniformity of sheet thickness on parts manufactured.The four factors including forming tool diameter,friction coefficient,press amount and feed were designed through the orthogonal test.The optimal parameters were obtained respectively on the forming of straight wall cylinders and box parts through the means method.The straight wall cylinders could have a better uniformity of sheet thickness by multi-pass incremental forming using tool diameter 9 mm,press amount 0.75 mm,friction coefficient 0.15 and feed 250 mm/min.The box parts could have a better uniformity of sheet thickness by multi-pass single point incremental forming using tool diameter 10 mm,press amount 0.5 mm,friction coefficient 0.175 and feed 250 mm/min.