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Materials Science in Additive Manufacturing                            Cast and 3D-printed fiber orientations



            Appendices                                           Substituting Equation AI into Equation AIV:

            Appendix A: Analytical result of one-dimensional                   ZV cos    Pz, d
                                                                                    f
                                                                        ,


            boundary constraints                               Num z,   d     r   2     2 Pz, d  (AV)

              For a 1D case with thickness Z, the amount of fiber per                 f    0
            unit length and width can be computed by:            Then, the total number of fibers crossing this plane at a
                ZV                                             given angle can be integrated through the thickness:
            N     f                                   (AI)
                 lr 2                                         Num 0,Z     d    2  0  Z  2 Num ,z     ,   d  dz

                                                                         ,

                                                                            ,
                  ff
              This volume can be divided into two regions, that                                     (AVI)
            us, Region 1 (z < l/2and Region 2 (z≥ l/2), as shown in   Substituting Equation AV into Equation AVI:
                           f
                                             f
            Figure A1, where z is the distance from the boundary. For
            different cases, Region 2 may not exist. For Region 1, the             2ZV f  cos
                                                                         ,
                                                                            ,


            total length of the distribution arc is:           Num0,Z      d     r   f 2

            Pz,
                                                                        ,
                                                                Z 2    Pz  d
            
 
         l                            z           2        dz                     (AVII)
                        f   sin 2        arcsin       0    Pz   d
                                                                          ,
                         2                       l   f  2      0


              l                 z               z       Let  w=z/(l/2)  be  the  dimensionless  coordinate,
                                                                           f
                 f    sinn  2   4 arccos  l      arcsin  l     Equations AII and AIII can be combined as:

                2            f  sin 2  
     f  2   Pw,

                                                      (AII)    	        sin 2         w 1 or  w sin
              For Region 2, the total length of the distribution arc is:        w





            Pz,     l   f     sin 2      (AIII)     sin  2   4 arccos    sin   w  
1 and  w  
 sin (AVIII)

                      2
                                                                 and Equation (AVII) can be rewritten as:
              If the distance between the fiber center and one specific              2ZV  cos

            cross-section plane is more than ±lcosθ/2, the fiber cannot   Num0,Z   d     f
                                                                            ,
                                                                         ,


                                       f
            pass through the plane. Thus, the number of fibers crossing                  r   f 2
            this plane at a given angle can be computed for any distance     Pw
                                                                            d
                                                                         ,
            z from the boundary:                                0 Zl f       2 Pw     dw         (AIX)
                                           Pz,

                                   f
            Num z,   d   N  2  l cos    2   d  (AIV)    0    ,    d
                     ,



                                     2
                                           0  Pz, d          For a specific position in region 1, where  u <1 :

                                                                 2 Pw,     arcsin w P w,   2  Pw,


                                                                0      d    0       d   arcsin w  d
                                                                             0 0  arcsinw   2  sin d

                                                                                               w

                                                                              2
                                                                             arcsiinw 	    
   4arccos     sin 
 sin  d
                                                                                  2





                                                                                                         (AX)
                                                                 Let θ =arcsinw and integrate into Equation AX:
                                                                     w

                                                                 2 Pw,     u
                                                                0      d    0   2  sin d

                                                                             2 	         w
                                                                               
 
  2   4 arccos   
 sin  d
                                                                             u    	       sin
                                                                                   2         w

                                                                             2   4   sinarccos   
 d (AXI)
            Figure A1. The schematic of 1D case with two different regions.        u        sin
            Volume 2 Issue 3 (2023)                         18                      https://doi.org/10.36922/msam.1603
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