To provide processing guidelines for manufacturing metal – thermoplastic composites joints employing a co-consolidation process. The guidelines focus on metal pre-treatment methods as well as on processing conditions, both of which need to be optimized on order to achieve the desired joint performance.
Keywords: co-consolidation, metal surface treatment, metal-thermoplastic bonding, mechanical interlocking
Apart from monolithic composite – composite joints, multi material joints are commonplace in modern light-weight structures. Metal inserts can be used in thermoplastic composite structures for load transfer purposes and to ease multi material assembly. The inserts can be co-consolidated or co-molded with thermoplastic composite material. The thermoplastic matrix material, already present in the prepreg, is thus used for bonding and no additional adhesives are employed and no composite pre-treatment is required.
The strength of the metal-composite interface, which is a crucial factor that affects the performance of the entire hybrid joint, can be tailored by choosing the appropriate metal pre-treatment methods and processing conditions. A predictable and robust joint behavior requires a proper understanding of physical mechanisms underlying the interface strength development. Within this project, these mechanisms are investigated for titanium – C/PEEK hybrid joints using a combination of experimental and analytical work.
The physical mechanisms governing the performance of co-consolidated titanium – C/PEEK joints are investigated experimentally. For this purpose, a fracture mechanics based test methodology was developed. The test method involves peeling of a thermoplastic composite tape from a metal substrate with help of a mandrel to prevent tape breakage. The specimens comprise a unidirectional fiber reinforced tape which was co-consolidated on a metal substrate using an autoclave process. Elaborate experiments are performed to study the effect of metal pre-treatment and molding cycle on the measured interfacial toughness. Extensive analytical surface analysis before molding and after testing helps to identify, isolate and analyse the governing mechanisms. Supported by micro-scale finite element models to study the effect of surface topography, these experiments results are finally translated to processing guidelines for hybrid titanium – C/PEEK joints.
- For more information please contact Sebastiaan Wijskamp.
- New thermoplastic composites materials
- Resin Systems
- Molding Compounds
- Fiber Placement
- Tailored Blanks
- Press Forming
- Welding Technologies