ECONOMIC PRODUCTION OF HOLLOW PARTS MADE OF THERMOPLASTIC COMPOSITES

摘要

Usually hollow or complex shaped parts are made in several manufacturing steps that always contain a joining step. In principle the joining of thermoplastic composites (TPC) could be integrated in the process, because during processing the thermoplastic matrix is molten. The molten state offers the opportunity to join complex shells together or furthermore to weld inserts in one shot. The modified diaphragm forming technique provides the possibility to form hollow structures or parts with undercuts in one shot without a joining step. In this process an inflatable bladder is placed into a TPC-preform made from commingled yarns which again is placed between two diaphragms. During the heating step the bladder membrane is inflated, in order to achieve a good heat transfer to the heated cavity. After the matrix is molten the whole setup is transferred into the next station, where the membrane is inflated again in order to form the preform into a cooled cavity. The paper will explain how this technique works in detail and will show its potential to produce complex parts in small batches at low costs.