On-line consolidation of filament wound thermoplastic parts

Abstract

A filament winding process for a melt-processable, thermoplastic matrix material, and a reinforcing fiber. The process is heat and pressure intensive. An on-line consolidation is provided.

We claim: 
     
       1. A method for filament winding fiber reinforced, thermoplastic, composite components, whereby void content is reduced, the method comprising the steps of: (a) providing a reinforcing fiber and a melt-processable, thermoplastic, matrix fiber;   (b) providing a mandrel upon which the component is formed;   (c) exerting a filament-spreading pressure on said reinforcing fiber and said matrix fiber prior to winding said fibers on to said mandrel;   (d) heating said matrix fiber to a thixotropic molten state by supplying heat to said matrix fiber from said mandrel, the temperature of said heat supplied from said mandrel ranging from about 60° Celsius below the melting point of said matrix fiber to just above the melting point of said matrix fiber, and supplying heat from a second source to said matrix fiber at an area of contact between said matrix fiber and said mandrel, the temperature of said second heat source to said area being above the melting point of the matrix fiber; and   (e) applying pressure to said external surface of said wound reinforcing fiber and said matrix fiber to induce shear to cause flow of the molten thermoplastic fiber and to provide an on-line consolidation of the component.   
     
     
       2. The filament winding process of claim 1, further comprising softening said thermoplastic matrix material prior to winding said thermoplastic matrix material onto said mandrel. 
     
     
       3. The filament winding process of claim 1, wherein laydown of said reinforcing fiber and said thermoplastic matrix material onto said mandrel is simultaneous. 
     
     
       4. The filament winding process of claim 1, wherein laydown of said thermoplastic matrix material onto said mandrel is prior to laydown of said reinforcing fiber. 
     
     
       5. The filament winding process of claim 1, further comprising, prior to forming a gas barrier layer, softening said thermoplastic fiber. 
     
     
       6. The filament winding process of claim 1, further comprising, after laydown of said reinforcing fiber and said thermoplastic matrix material onto said mandrel, forming a gas barrier layer on said mandrel. 
     
     
       7. The filament winding process of claim 1, wherein said thermoplastic matrix material is a thermotropic LCP. 
     
     
       8. The filament winding process of claim 1, wherein said reinforcing fiber is a glass fiber.