EFFECT OF TOOL TEMPERATURE ON LAMINATE PROPERTIES DURING IN SITU CONSOLIDATION PLACEMENT PROCESS

摘要

Thermoplastic tape placement is a discontinuous process. Fully impregnated fiber reinforced thermoplastic tapes are laid onto a mold to build up curved or plane structures sequentially. Each tape is melted by a heat source, welded to the layer below, compressed by e.g. a roller, and cooled down below the melt temperature. If this is done properly, in situ consolidation can be achieved, which means no additional consolidation process is needed.rnOver the whole process the material is heated and cooled several times. The resulting morphology of the laminate is strongly dependent on process parameters. Beside the main heater, the tool temperature is one of the major processing parameters influencing the resulting laminate quality. The effect of tool temperature on laminate properties during in situ consolidation placement process was studied with regard to the laminate morphology and subsequently residual stresses in the component (Figure 1).rnThe lecture deals with a short description of the placement process and the thermal model used. It explains the effect of tool temperature on peel resistance and interlaminar shear strength. Furthermore it discusses how the dependency of crystallization temperature on cooling rate effects deconsolidation and residual stresses. Optimized parameters to decrease residual stresses are proposed and confirmed by testing.