Leading edge specimens are required for performance testing in a high
heat flux test facility. The leading edges (LE) will be fabricated as
carbon-carbon (C-C) composites machined to final part dimensions. Two
different fiber architectures are required, but each leading edge
involves the use of an unbalanced carbon fabric with different fibers in
the warp and fill directions. The supplier must 1) procure the fabric,
2) assemble the fabric layup, 3) fabricate the carbon-carbon composite
using a pitch matrix (or equivalent) using a high graphitization
temperature, and 4) machine the parts to final dimensions. To insure
highest possible thermal conductivity, carbon-carbon

composites shall be fabricated using a combination of pitch matrix
densification and chemical vapor infiltration (CVI) process.  CVI shall
also be formed on post-machined parts to enhance mechanical strength of
leading edge components. Coatings are not required. The supplier will
deliver a total of four (4) LE specimens, two (2) of each architecture,
with each LE specimen eighteen (18) inches in width. The supplier will
also deliver a total of four (4) flat panels, two (2) of each
architecture, for material property testing and subsequent laboratory
environment coating evaluations.

Table 1 lists the specifications to be used by the supplier in procuring
the fabric.

Table 1. Preform construction for C-C leading edge specimens.

  -------------- ------------------------ ---------- ----------- -----------
  **Fabric No.   **0/90 K321/T300 3:1                            
  1**            5HS**                                           

                                                                 

                 Fiber Type               Tow Size   Ends/Inch   Direction

                 K321 (or P-30X)          2k         22.5        Warp

                 T-300                    3k         10.5        Fill

                                                                 

                 Fabric Style             5 HS                   

                 Areal Weight             \> 368                 
                                          g/m^2^                 

                                                                 

  **Fabric No.   **0/90 T300 1:1 5HS**                           
  2**                                                            

                                                                 

                 Fiber Type               Tow Size   Ends/Inch   Direction

                 T-300                    3k         16          Warp

                 T-300                    3k         16          Fill

                                                                 

                 Fabric Style             5 HS                   

                 Areal Weight             \> 252                 
                                          g/m^2^                 

                                                                 

  **Tape**       **0° K321**                                     

                                                                 

                 Fiber Type               Tow Size   Ends/Inch   Direction

                 K321 (or P-30X)          2k         22.5        0°

                                                                 

                 Areal Weight             \> 285                 
                                          g/m^2^                 
  -------------- ------------------------ ---------- ----------- -----------

Details and totals for the fabric area requirements are provided in
Table 2 below. The details of the C-C parts and processing are provided
in Table 3 below.

Table 2. Fabric and tape area requirements for construction of C-C
leading edge specimens and property panels.

  -------------------------- ----------------------- --------------------
  **Fabric No. 1**           **K321/T300 3:1 5HS**   

                                                     

  Part                       LE Specimen 1           Material Property
                                                     Panel 1

  Part Planar Dimensions     18 x 5                  10 x 10
  (inches)                                           

  Warp Width (inch)          18                      10

  Part Thickness (inch)      0.51                    0.2

  Plies Req\'d (#)           35                      14

  Fabric Planar Dimensions   18 x 5                  10 x 10
  (inches)                                           

  Ply Area (in^2^)           90                      100

  Area/Part                  3,150                   1,400

  Total Parts (#)            2                       2

  Total Ply Area (in^2^)     6,300                   2,800

                                                     

  **Total Req\'d Fabric Area **9,100**               **K321/T300 4:1
  (in^2^)**                                          5HS**

                                                     

  **Fabric No. 2**           **T300 1:1 5HS**        

                                                     

  Part                       LE Specimen 2           Material Property
                                                     Panel 2

  Part Planar Dimensions     18 x 5                  10 x 10
  (inches)                                           

  Warp Width (inch)          18                      10

  Part Thickness (inch)      0.51                    0.2

  Fabric Planar Dimensions   (5+18)/(2\^0.5) x       10\*(2\^0.5) x
  (inches)                   (5+18)/(2\^0.5)         10\*(2\^0.5)

  Plies Req\'d (#)           26                      10

  Ply Area (in^2^)           265                     200

  Area/Part                  6,877                   2,000

  Total Parts (#)            2                       2

  Total Ply Area (in^2^)     13,754                  4,000

                                                     

  **Total Req\'d Fabric Area **17,754**              **T300 1:1 5HS**
  (in^2^)**                                          

                                                     

  **Tape**                   **0° K321**             

                                                     

  Part                       LE Specimen 2           Material Property
                                                     Panel 2

  Part Planar Dimensions     18 x 5                  10 x 10
  (inches)                                           

  Warp Width (inch)          18                      10

  Part Thickness (inch)      0.51                    0.2

  Plies Req\'d (#)           26                      10

  Fabric Planar Dimensions   18 x 5                  10 x 10
  (inches)                                           

  Ply Area (in^2^)           90                      100

  Area/Part                  2,340                   1,000

  Total Parts (#)            2                       2

  Total Ply Area (in^2^)     4,680                   2,000

                                                     

  **Total Req\'d Tape Area   **6,680**               **K321/T300 4:1
  (in^2^)**                                          5HS**
  -------------------------- ----------------------- --------------------

Table 3. C-C leading edge and property panels part and processing
requirements.

![](media/image1.wmf){width="7.75in" height="2.4409722222222223in"}

Figure 1 provides finished part dimensions for the leading edge
specimens. The cutting plan for the material property testing panel is
included for reference as Figure 2. The supplier should machine one of
the two flat material property panels of each fiber architecture. NASA
LaRC will use the second flat material property panel for high
temperature coating evaluations.

The list of contract deliverables is itemized in Table 4.

# Sharp Passive Leading Edge Geometry

![](media/image2.wmf){width="4.766666666666667in"
height="0.5138888888888888in"}

# Tip Region Close-up

![](media/image3.wmf){width="1.2361111111111112in"
height="2.6680555555555556in"}

![](media/image4.png){width="5.995833333333334in"
height="5.584722222222222in"}

Figure 2. Cutting plan to be used to machine material property specimens
from one of two flat C-C panels made for each fiber architecture.

Table 4. List of contract deliverables.

+----------------------------------------------+-----------------------+
| **Layup Architecture**                       | **C-C Parts to be     |
|                                              | delivered**           |
+----------------------------------------------+-----------------------+
| (0/90 K321/T300 3:1)~35~                     | 2 LE specimens^1^     |
+----------------------------------------------+-----------------------+
| (0/90 K321/T300 3:1)~14~                     | 1-10"x10" flat panel  |
|                                              | plus                  |
|                                              |                       |
|                                              | 38 coupon             |
|                                              | specimens^2^          |
+----------------------------------------------+-----------------------+
| \[(±45 T300/0 K321/-,+45 T300/0 K321)~6~(±45 | 2 LE specimens^1^     |
| T300/0 K321)\]S                              |                       |
+----------------------------------------------+-----------------------+
| \[(±45 T300/0 K321/-,+45 T300/0 K321)~2~(±45 | 1-10"x10" flat panel  |
| T300/0 K321)\]S                              | plus                  |
|                                              |                       |
|                                              | 38 coupon             |
|                                              | specimens^2^          |
+----------------------------------------------+-----------------------+

^1^ Final part geometry is detailed in Figure 1. Width of each LE
specimen is 18 inches.

^2^ Coupons to be machined from second 10"x10" using cutting plan of
Figure 2. 38 coupon specimens include 9 fill compression, 9 warp
compression, 8 warp conductivity, 8 fill conductivity, 2 warp thermal
expansion, and 2 fill thermal expansion.