Curved Composite Part Moulding with Flexible Silicone Mandrel
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing curved composite parts, such as those with angled cross-sections, require costly and complex automation, resulting in low productivity and mediocre mechanical performance due to inhomogeneous fiber alignment.
Innovation Solution
A process involving pre-impregnated and pre-compacted composite strips with unidirectional fibers, applied to a flexible silicone mandrel and then a heated metal tool, allowing for vacuum compaction and shaping to achieve a curved form, followed by polymerization, which enhances mechanical performance through homogeneous draping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If progressive draping of impregnated fabrics by hand or robot is used, then precise yarn placement is achieved, but device complexity and cost increase significantly
Solution Approach 1:
The fabric is pre-impregnated with resin and pre-formed into a flat composite strip before being applied to the mandrel. This preliminary preparation eliminates the need for complex real-time impregnation and placement systems, while still achieving precise fiber orientation through the predetermined strip configuration.
Solution Approach 2:
The invention extracts the complex draping operation from the manufacturing process by using a pre-formed composite strip that already contains the desired fiber orientation. The strip is simply applied to the mandrel and cured, removing the need for progressive draping equipment while maintaining fiber placement precision.
2Strength
If robot-based yarn-by-wire draping is used, then mechanical performance is optimized, but productivity decreases due to reduced rates
Solution Approach 1:
The composite strip is pre-manufactured with optimized fiber orientation and resin impregnation before being applied to the mandrel. This allows the strip to be prepared in advance with precise fiber alignment for optimal mechanical performance, while the actual molding process becomes a simple, fast application and curing operation that increases productivity.
3Area of stationary object
If fan-like opening of fibers is used in traditional draping, then fiber coverage is achieved, but homogeneity of fiber distribution deteriorates
Solution Approach 1:
The flat composite strip is designed with uniform fiber distribution and consistent resin impregnation throughout its structure. When applied to the mandrel, this homogeneous structure is preserved, eliminating the fan-like opening effect that creates non-uniform fiber distribution in traditional draping methods.
4Manufacturing precision
If complex automation systems are implemented, then manufacturing precision is improved, but manufacturing cost increases
Solution Approach 1:
The invention extracts the precision manufacturing requirements from the molding process itself and transfers them to the pre-manufacturing of the composite strip. This allows standard, cost-effective molding equipment to be used, while the precision is achieved during strip fabrication through controlled fiber placement and resin impregnation processes.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enables the production of composite parts with exceptional resistance and improved mechanical performance while reducing costs and simplifying the process, allowing for repetitive and efficient manufacturing of parts with complex geometries.
Implementation Method 1
By flexible mandrel is meant a deformable mandrel between a rectilinear position and a curved position
Implementation Method 2
by compacting under vacuum at a second temperature
Implementation Method 3
deposited on a heated metal tool having in curve the complementary shape of the mandrel
Implementation Method 4
the mold is put under pressure and temperature on the assembly thus obtained for polymerization
Data Source
Figure 1~3
Figure 4~6
Figure 7~9
AI summary
The invention relates to a method and device for moulding a curved part made from composite material and to the resulting part, in which the part is made from at least one composite band (24) formed by at least two laps (3, 4, 5) of unidirectional reinforcing fibres preimpregnated with resin and pre-compacted against one another. The band is applied longitudinally to a flexible silicone mandrel (13) by means of vacuum compaction in order to confer thereon the shape of the mandrel and the resulting band (24) is deposited on a heated metal tool (31) having a curve that complements the shape of the mandrel and forming the core (32) of a temperature and pressure application mould (26). The flexible mandrel is removed, polymerisation pressure and temperature are applied to the mould and the part is removed after cooling.