Deformation Behavior in High-Aspect Hole Punching into Ceramic Green Sheets Plastic Working of Ceramic Green Sheets IV

摘要

In the production of a mutilayer ceramic circuitboard, shearing, hole punching and hot-press lamination ofceramic green sheets are needed as the accurate plastic working.Hundreds of thousands of high-aspect holes have to be punchedinto ceramic green sheets. Minor deformations around the holesdue to punching cause low-accuracy hole positions andundesired deformations in the ceramic green sheets. Todetermine the deformation mechanism involved in punchinghigh-aspect holes in ceramic green sheets, a large-scale modelwas examined and confirmed to be satisfactory for studying thedeformation mechanism in high-aspect hole punching. It isclarified that deformation in high-aspect hole punching occursduring punch insertion. The deformation value is about twicethat for pure copper. This deformation can be reduced byincreasing thc clearance between the punch and die to more than6 percent and by increasing the punching speed.