METHOD FOR DRILLING HOLE ON PLATE STACK

摘要

PROBLEM TO BE SOLVED: To drill a hole having good fillability of resin paste containing metal powder even, when drilling aΦ0.6 mm or less through hole on plate stack having a larger coefficient of thermal expansion at a core layer than that at a surface layer including composite plate stack. SOLUTION: An under cut type drill is used for drilling a through hole ofΦ0.6 mm or less on plate stack. Friction between a drill and the plate stack is low and the through hole can be drilled with keeping a condition that thermal expansion of the stack core layer is low. Diameter of the undercut type drill 1 gradually increases from a tip to a designated position and then decreases again. The small diameter evenly continues to a base part of the drill 1. COPYRIGHT: (C)2004,JPO