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Advantages of the braiding process for Carbon / Carbon and Carbon / SIC Ceramics

 
 
The braiding process is one of the most practical 
and efficient manufacturing methods available to the 
composites industry today.  Braiding allows for the custom 
combination of continuous fibers in an oriented pattern 
over a tool or form (called a “mandrel”) of nearly any shape 
or size, eliminating the need for cuts, splices, or darts 
inherent with other composite fabrication methods.  When 
creating a braided shape (referred to as “preform”), the 
fiber is applied to the tool under tension, thus eliminating 
wrinkles and forgoing a need for multiple de-bulk cycles 
which are common with alternative hand layup prepreg 
fabrication.   
 
 
 The triaxial braiding process creates a single ply of 
tubular fabric by interlacing both helical (+/-) and axial (0°) 
yarns.  In this instance, three (3) yarns are interlaced – two 
helical and one axial. The helical yarns provide off-axis or 
hoop reinforcement while the axial yarns provide 0° 
reinforcement parallel to the center axis of the part.  Since 
the size, modulus, and quantity of the various yarns can be 
customized, the design of the resultant structure can be 
truly optimized.  Triaxial braid can be constructed as a 
quasi-isotropic laminate, with similar material properties in 
all directions, or designed to add strength / stiffness only 
where needed to reduce weight.
 
One can think of braiding as a continuous fiber fabric shaping and placement process. 
In general, the process is similar to plastic extrusion and can be controlled by the rate at which 
the braid is pulled relative to the speed of formation.  This allows for NC programmable control 
to be used to specify the extrusion rate, which in turn determines and maintains the desired tow 
orientation throughout the part. 
 
 
 
 
 
 
 
 
 
Advantages Specific to Ceramics & Other High Temperature Composites 
 
 The braiding process allows for a wide range of 
materials and tow sizes to be used as a laminate 
reinforcement.  Often times the vapor deposition 
process, as well as more standard infiltration methods, 
are aided by using preforms with intentional gaps 
between the tows. Braiding allows for the use of smaller 
3k and, in some cases, 1k carbon tows where gaps 
between tows can be incorporated into the design in 
order to improve various densification methods. 
 
 
 
 Another advantage to braiding for ceramics is the 
ability to easily create continuous, conical and tapered 
geometries.  Braiding is conducive to creating preforms 
of cone-like shapes for subsequent manufacturing of 
high temperature thrusters, nozzles, rocket motors, and 
other complex geometries.  Because the braid angle 
can be controlled throughout the tapered regions, 
engineers can ensure that all thermal and structural 
requirements are satisfied, as well as allowing for more 
efficient densification. 
 
 
 
 
 
 
 
 
 
Braiding allows designers to create quasi-isotropic or customized fabrics 
  • Independent control of helical tow orientation as well as ability to select dis-similar fibers 
Triaxial braid constructions are considered more damage tolerant 
 
  • Braid is formed over a wide range of geometries without the need for ply darting and splices 
Braiding increases efficiency and improves accuracy 
 
  • Braid formation for any given region is machine controlled and requires little to no “touch labor” 
  • NC Control is used to ensure accuracy and repeatability 

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