Tows and Courses

AFP Machine #1

AFP Machine #2

Enclosure

Autoclave

Tows and Courses

Image right: On the Fiber Placement Machine, courses are generally placed in orientations of 0°, +45°, -45° and 90° to build up plies. Image Credit: LMSSC-MO.

One might say that Fiber Placement is an automated composites manufacturing process of heating and compacting resin pre-impregnated non-metallic fibers on typically complex tooling mandrels. The fiber usually comes in the form of what are referred to as "tows". A tow is typically a bundle of carbon fibers impregnated with epoxy resin and is approximately 0.125" wide by 0.005" thick and comes on a spool. Fiber placement machines (FPM) generally have a capacity of 12 to 32 tows or when placing all tows at a time in a course, have respective course widths of 1.5" to 4". The tows are fed to a heater and compaction roller on the FPM head and through robotic type machine movements, are placed in courses across a tool surface. Courses are generally placed in orientations of 0°, +45°, -45° and 90° to build up plies which in combination, have good properties in all directions. In addition, the machine can drop and add tows at any time to meet the specific circumstances of the shape it is placing on. In the photo at right you can discern individual courses of tows.