DOUBLE-DIAPHRAGM FORMING OF ADVANCED COMPOSITE SHAPES WITH ACTIVE TOOL SHAPE AND TEMPERATURE CONTROL

摘要

Double-Diaphragm Forming (DDF) is a manufacturing process whereby a flat, uncured advanced composite laminate is sandwiched between two compliant diaphragms, heated to facilitate inter- and intra-ply movement, and then vacuum formed over a tool. Recent process improvements to help increase the range of defect free part shapes that can be formed using DDF include a reconfigurable (active) tool, which can change shape incrementally in real time, and heating of the laminate with a multi-zone heating blanket. DDF trials performed over fixed and active shapes using continuous fiber carbon/epoxy lay-ups clearly demonstrate these improvements, but results appear to be shape dependent.