A cure for processing problems
High-tech composites for the aerospace industry have significantly enhanced the performance and functionality of aircraft components while decreasing weight, fuel consumption and emissions. However, many question whether use of the curing process is justified given its energy voracity and a lack of adequate control over processing parameters. Thanks to knowledge-based optimisation software developed with EU support of the project OPTO-CLAVE, manufacturers of high-quality structural composite components can use their autoclaves much more effectively and efficiently. Numerical methods describing materials behaviours, including the cure kinetics of relevant resin systems, together with a novel methodology to determine glass transition temperature were fundamental to the system identification component. It takes into consideration autoclave dimensions, composite part geometry, materials specifications, the material state models and real temperature data from previous runs. The system identification module then calculates the heat transfer algorithm of the autoclave that is needed for the subsequent optimisation step. The heat transfer model is expected to be marketable as a stand-alone component where targets include the automotive and wind energy sectors, in addition to aerospace. Optimisation takes into account materials and process constraints through a cure profile optimisation algorithm that is also planned to be marketed as a stand-alone version. The DETA-LEARN software, incorporating both system identification and optimisation algorithms, also estimates energy usage for a given cycle. The optimisation algorithm selects among alternative cure cycles to find the one reducing processing time or energy usage while achieving required materials specifications. OPTO-CLAVE has provided an important process optimisation suite to manufacturers of high-quality composites that relay on autoclaves for curing of resins. Use of the software for the production of a composite stiffened panel decreased cure time by 12 % and energy consumption by 16 %. scientists are planning to integrate the DETA-LEARN software with the partner's existing DETA-SCOPE (Dielectric Thermal Analysis & Spectroscopic Evaluation of Polymerisation Reactions) monitoring system. DETA-SCOPE was developed and is marketed to manufacturers exploiting the curing processes. The combination will ensure instant market penetration with targeted industrial groups in the aeronautical, automotive and wind energy sectors.
