Abstract:
A process for marking a composite panel prior to curing for subsequent identification. An illustrative embodiment of the process includes applying a label strip made of a resin-permeable material to a composite panel formed of a resin and curing the panel to an elevated temperature such that the resin at least partially permeates the label strip. A marked composite panel is also disclosed.

Description:
TECHNICAL FIELD 
       [0001]    The disclosure generally relates to test coupons. More particularly, the disclosure relates to a process for marking a composite panel in which label strips become a part of the composite panel from which test coupons are fabricated. 
       BACKGROUND 
       [0002]    The traditional test coupon labeling method includes painting of labels on the panels by hand prior to sectioning of the test coupons from a larger panel. Because technicians may hand-label hundreds of similar coupons with often verbose coded language, mistakes may be unavoidable. Therefore, the painted labels are typically sent to Quality Assurance (QA) for double-checking. However, the painted labels may be washed off by cutting fluids or may be damaged during handling, potentially rendering the labels unreadable during testing. 
       SUMMARY 
       [0003]    The disclosure is generally directed to a process for marking a composite panel prior to curing for subsequent identification. An illustrative embodiment of the process includes applying a label strip made of a resin-permeable material to a composite panel formed of a resin and curing the panel to an elevated temperature such that the resin at least partially permeates the label strip. 
         [0004]    The disclosure is further generally directed to a marked composite panel. An illustrative embodiment of the marked composite panel includes a composite panel formed of a resin and at least one resin-permeable label strip formed into the composite panel. The resin of the composite panel at least partially permeates the at least one resin-permeable label strip. 
     
    
     
       BRIEF DESCRIPTION OF THE ILLUSTRATIONS 
         [0005]      FIG. 1  is a top view of a composite panel. 
           [0006]      FIG. 2  is a top view of a template, placed on the composite panel (not shown). 
           [0007]      FIG. 3  is an edge view of the template placed on the composite panel. 
           [0008]      FIG. 4  is a top view of the template, more particularly illustrating drawing of multiple scribe lines and label-positioning lines on the adjacent composite panel using a marking implement. 
           [0009]      FIG. 5  is a top view of the composite panel, with multiple scribe lines and label-positioning lines drawn thereon. 
           [0010]      FIG. 6  is a top view of the composite panel, with multiple label strips placed on the composite panel. 
           [0011]      FIG. 7  is a top view of a caul plate, placed on the composite panel (not shown). 
           [0012]      FIG. 8  is an edge view of the caul plate placed on the composite panel. 
           [0013]      FIG. 9  is a top view of the composite panel, with multiple cutting lines provided along the respective scribe lines in the composite panel. 
           [0014]      FIG. 10  is a front view of a coupon cut from the composite panel, with a label strip provided on the coupon. 
           [0015]      FIG. 11  is a front view of a coupon, with a pair of grips provided on the coupon preparatory to testing. 
           [0016]      FIG. 12  is a flow diagram showing an illustrative embodiment of the composite panel marking process. 
           [0017]      FIG. 13  is a flow diagram of an aircraft production and service methodology. 
           [0018]      FIG. 14  is a block diagram of an aircraft. 
           [0019]      FIG. 15  is a schematic diagram illustrating an exemplary process for curing of a composite panel. 
           [0020]      FIG. 16  is a block diagram illustrating an exemplary process for curing of a composite panel. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    Referring initially to  FIGS. 1-11 ,  15  and  16 , an illustrative embodiment of the composite coupon labeling process, hereinafter process, is shown. As shown in  FIG. 1 , the process includes providing a composite panel  1  which may be laminated and have a selected number of plies at any of various orientations and sequences. The composite panel  1  may have a fixed straight edge  2 . The fixed straight edge  2  is useful in precisely orienting and locating the plies of the composite panel  1 . 
         [0022]    As shown in  FIGS. 2 and 3 , a scribing template  6  may be placed on the composite panel  1 . Edges  6   a  of the scribing template  6  may be used to orient the scribing template  6  on the composite panel  1 . The scribing template  6  may be, for example and without limitation, a 0.030″ aluminum sheet. Multiple longitudinal scribe slots  7  may extend through the scribing template  6  in generally parallel, spaced-apart relationship with respect to each other. A first set of transverse scribe slots  8  may extend through the scribing template  6 , to one end of and generally between the adjacent longitudinal scribe slots  7 . Each of the first set of transverse scribe slots  8  may be oriented in generally perpendicular relationship with respect to each longitudinal scribe slot  7 . A second set of transverse scribe slots  9  may extend through the scribing template  6 , to the other end of and generally between the adjacent longitudinal scribe slots  7 . Each of the second set of transverse scribe slots  9  may be oriented in generally perpendicular relationship with respect to each longitudinal scribe slot  7 . 
         [0023]    The longitudinal scribe slots  7 , the first set of transverse scribe slots  8  and the second set of transverse scribe slots  9  may define respective edges of test coupons  28  ( FIG. 5 ) which will subsequently be cut out of the composite panel  1 . The layout of the longitudinal scribe slots  7  and the transverse scribe slots  8  and  9  which will ultimately form the edges  28   a  of the test coupons  28  may be generated using a CAD system at 0.13 inch or other spacing to allow for the kerf of a diamond saw that may be used to cut the composite panel  1  into the test coupons  28 . Multiple label-positioning scribe slots  10  may extend through the scribing template  6 , between the adjacent longitudinal scribe slots  7  and in generally parallel, spaced-apart relationship with respect to the respective ones of the first set of transverse scribe slots  8 . The longitudinal scribe slots  7 , the first set of transverse scribe slots  8 , the second set of transverse scribe slots  9  and the label-positioning scribe slots  10  may be without limitation water jet-machined in the scribing template  6 , for example. 
         [0024]    As shown in  FIGS. 4 and 5 , a marking implement  14  ( FIG. 4 ) may be extended through and along each longitudinal scribe slot  7  to draw longitudinal scribe lines  17  on the composite panel  1 . In similar manner, the marking implement  14  may be extended through and along each of the first set of transverse scribe slots  8 ; each of the second set of transverse scribe slots  9 ; and each label-positioning slot  10  to draw a first set of transverse scribe lines  18 ; a second set of transverse scribe lines  19 ; and label-positioning lines  20 , respectively, on the composite panel  1 . The marking implement  14  may be, for example and without limitation, a silver marking pencil. After the first set of transverse scribe lines  18 , the second set of transverse scribe lines  19  and the label-positioning lines  20  may be drawn on the composite panel  1 . The scribing template  6  may then be removed from the composite panel  1 , as shown in  FIG. 5 . 
         [0025]    As shown in  FIG. 6 , multiple label strips  24  may be provided on the composite panel  1 . Each label strip  24  may be provided between each corresponding pair of adjacent longitudinal scribe lines  17 , along and adjacent to the corresponding label-positioning line  20 . Side edges of each label strip  24  may be generally aligned with the respective longitudinal scribe lines  17 . Identifying indicia (not numbered) may be provided on each label strip  24  to identify each of multiple test coupons which will be subsequently cut from the composite panel  1  along the longitudinal scribe lines  17 , the first set of transverse scribe lines  18  and the second set of transverse scribe lines  19 , as will be hereinafter described. 
         [0026]    The label strips  24  and any identifying indicia thereon may be printed to proper dimensions (such as size 10-14 font, for example) on 11×17 sheets of a resin-permeable material such as paper using an EXCEL spreadsheet, for example, and cut from the sheet of paper. Printing of the identifying indicia on the label strips  24  serializes the identifying indicia of the label strips  24  while eliminating mistakes. Moreover, printing of the identifying indicia on the label strips  24  prevents smudging and illegibility which are common characteristics of hand-printing. The identifying indicia which are provided on each label strip  24  may include custom bar codes to expedite identification. The label strips  24  may be attached to the composite layer  1  according to any suitable technique which is known to those skilled in the art. For example, the label strips  24  may be affixed to the composite layer  1  by the application of heat and manual pressure. 
         [0027]    As shown in  FIGS. 7 and 8 , a caul plate  26  may be placed on the composite panel  1  for curing purposes. The caul plate  26  may be without limitation a 0.125″ aluminum caul plate, for example. The composite panel  1  with the caul plate  26  placed thereon may then be cured. An exemplary curing process is shown in  FIG. 15  and in block diagram form in  FIG. 16 . The process includes (1) applying a film release  36  between the caul plate  26  and the composite panel  1 , as shown in  FIG. 15  and indicated in block  1602  in  FIG. 16 ; (2) applying a breather  38  over the caul plate  26  (block  1604 ); (3) applying vacuum bagging  40  and ports  41  over the breather  38  (block  1606 ); (4) sealing the vacuum bagging  40  and ports  41  to a support  42  such as a plate or table on which the composite panel  1  is to be cured (block  1608 ); (5) placing the assembly  46  in an autoclave  44  and applying vacuum pressure (block  1610 ); applying heat and pressure at ramp-up rates, pausing at the gel temperature of the resin and venting to atmosphere if necessary (block  1612 ); (6) ramping down heat and pressure and removing the assembly  46  from the autoclave  44  (block  1614 ); and (8) removing the vacuum bagging  40  and ports  41  and breather  38 . During the curing process, resin may soak into the typical paper label strips  24 , rendering the label strips  24  a permanent or integral part of the composite panel  1  and resistant or impervious to solvents, abrasion, rubbing, smudging, etc. 
         [0028]    As shown in  FIG. 9 , individual test coupons  28  may be cut from the composite panel  1  by sawing the composite panel  1  along longitudinal cutting lines  17   a  and transverse cutting lines  18   a  and  19   a , respectively. The longitudinal cutting lines  17   a  may generally coincide with the respective longitudinal scribe lines  17 , whereas the transverse cutting lines  18   a  and  19   a  may generally coincide with the respective first set of transverse scribe lines  18  and second set of transverse scribe lines  19 . The label strips  24  remain on the respective test coupons  28 . Therefore, each test coupon  28  typically does not require individual additional labeling. 
         [0029]    As illustrated in  FIG. 10 , a coupon opening  29  may be drilled in each test coupon  28 . The coupon opening  29  may extend through generally the center of the test coupon  28 . Test coupons  28  may be drilled in stacks of up to five (5) without deterioration of the coupon opening  29 , provided a carbon backing (not shown) is used. 
         [0030]    As illustrated in  FIG. 11 , a grip  32  may be provided on each end of each test coupon  28  for testing purposes. The label strip  24  may be positioned in such a manner that each grip  32  does not interfere with reading of the label strip  24 . Each test coupon  28  may be subjected to testing in the conventional manner. 
         [0031]    Referring next to  FIG. 12 , a flow diagram  1200  which summarizes an illustrative embodiment of the composite coupon labeling process is shown. In block  1202 , a layout of the test coupons may be generated using a CAD system. In block  1204 , a scribing template may be created using the CAD data obtained in block  1202 . In block  1206 , a composite panel may be laid up. In block  1208 , coupon scribe lines may be drawn out or traced onto the composite panel using the scribing template. In block  1210 , labels may be printed and then cut into strips. In block  1212 , the label strips may be placed and aligned on the composite panel. In block  1214 , the composite panel may be cured. In block  1216 , the composite panel may be cut along the scribe lines to create individual coupons. 
         [0032]    Referring next to  FIGS. 13 and 14 , embodiments of the disclosure may be used in the context of an aircraft manufacturing and service method  78  as shown in  FIG. 13  and an aircraft  94  as shown in  FIG. 14 . During pre-production, exemplary method  78  may include specification and design  80  of the aircraft  94  and material procurement  82 . During production, component and subassembly manufacturing  84  and system integration  86  of the aircraft  94  takes place. Thereafter, the aircraft  94  may go through certification and delivery  88  in order to be placed in service  90 . While in service by a customer, the aircraft  94  may be scheduled for routine maintenance and service  90  (which may also include modification, reconfiguration, refurbishment, and so on). 
         [0033]    Each of the processes of method  78  may be performed or carried out by a system integrator, a third party, and/or an operator (e.g., a customer). For the purposes of this description, a system integrator may include without limitation any number of aircraft manufacturers and major-system subcontractors; a third party may include without limitation any number of vendors, subcontractors, and suppliers; and an operator may be an airline, leasing company, military entity, service organization, and so on. 
         [0034]    As shown in  FIG. 14 , the aircraft  94  produced by exemplary method  78  may include an airframe  98  with a plurality of systems  96  and an interior  100 . Examples of high-level systems  96  may include one or more of a propulsion system  102 , an electrical system  104 , a hydraulic system  106 , and an environmental system  108 . Any number of other systems may be included. Although an aerospace example is shown, the principles of the disclosure may be applied to other industries, such as the automotive industry. 
         [0035]    The apparatus embodied herein may be employed during any one or more of the stages of the production and service method  78 . For example, components or subassemblies corresponding to production process  84  may be fabricated or manufactured in a manner similar to components or subassemblies produced while the aircraft  94  is in service. Also, one or more apparatus embodiments may be utilized during the production stages  84  and  86 , for example, by substantially expediting assembly of or reducing the cost of an aircraft  94 . Similarly, one or more apparatus embodiments may be utilized while the aircraft  94  is in service, for example and without limitation, to maintenance and service  92 . 
         [0036]    Although the embodiments of this disclosure have been described with respect to certain exemplary embodiments, it is to be understood that the specific embodiments are for purposes of illustration and not limitation, as other variations will occur to those of skill in the art.