## 4 Case study
### Preliminary Analysis Application
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & **I1 = \(\sigma\)/\(\rho\)** & **I2 = \(\sigma\)/\(\rho\)** & **I4 = E/\(\rho\)** & **I5 = E° (1/2)/\(\rho\)** & **I6 = \(\sigma\)/\((\rho\)*C)** & **I7 = E/(\(\rho\)*C)** \\ \hline
**Material** & **MIN** & **MAX** & **MIN** & **MAX** & **MIN** & **MAX** & **MIN** & **MAX** & **MIN** & **MAX** \\ \hline LaserForm AlSi12 & 171,642 & 186,567 & 93,284 & 108,209 & 0 & 0 & 26,119 & 27,985 & 3122 & 3231 & 1333 & 1546 \\ LaserForm AlSi7 MgO.6 & 131,086 & 161,049 & 78,652 & 101,124 & 0 & 0 & 26,217 & 26,966 & 314 & 3178 & 1269 & 1631 \\ LaserForm AlSi7 MgO.6 (DA) & 149,813 & 172,285 & 108,614 & 123,596 & 0 & 0 & 27,344 & 27,715 & 3200 & 3222 & 1724 & 1962 \\ AlSi10 Mg (HT) & 131,086 & 161,049 & 86,142 & 112,360 & 0 & 0 & 22,472 & 24,345 & 2901 & 3020 & 1305 & 1702 \\ CL 3041 (AlSi12) (SR) & 116,105 & 121,723 & 63,670 & 82,397 & 0 & 0 & 28,090 & 28,090 & 3244 & 3244 & 936 & 1212 \\ CL 3241 (AlSi10 Mg) (HT) & 126,217 & 132,275 & 703,034 & 88,015 & 0 & 0 & 28,090 & 28,090 & 3244 & 3244 & 1124 & 1354 \\ EOS AlSi10 Mg & 164,794 & 179,775 & 86,142 & 104,869 & 0 & 0 & 24,345 & 31,835 & 3020 & 3453 & 1363 \\ EOS AlSi10 Mg (SR) & 125,468 & 134,831 & 80,524 & 91,760 & 0 & 18,727 & 29,963 & 2648 & 3350 & 1220 & 1390 \\ AlSi10 Mg & 133,708 & 149,064 & 78,277 & 89,513 & 0 & 0 & 26,966 & 31,461 & 3178 & 3433 & 1263 & 1444 \\ Laserform 17-4 PH (HT) & 177,333 & 188,000 & 156,000 & 174,667 & 28,000 & 32,000 & 25,333 & 28,000 & 1838 & 1952 & 2600 & 2911 \\ Managing steel & 137,500 & 137,500 & 116,250 & 116,250 & 42,875 & 76,875 & 17,500 & 17,500 & 1479 & 1479 & 2114 & 2114 \\ CL 91 RW (HT) & 212,500 & 212,500 & 200,000 & 200,000 & 300,000 & 31,250 & 25,000 & 25,000 & 1768 & 1768 & 274 & 2740 \\
17-4 PH SS & 130,250 & 130,250 & 82,500 & 82,500 & 27,500 & 31,250 & 24,375 & 24,375 & 1746 & 1746 & 1650 & 1650 \\ EOS Maraging steel & 125,000 & 150,000 & 112,500 & 143,750 & 42,875 & 76,875 & 16,875 & 23,125 & 1452 & 1700 & 1607 & 2054 \\ CL 91 RW (HT) & 212,500 & 212,500 & 200,000 & 200,000 & 30,000 & 31,250 & 25,000 & 25,000 & 1768 & 1768 & 274 & 2740 \\ SLM Solution 1.2709 & 121,500 & 131,250 & 95,125 & 114,125 & 91,500 & 91,500 & 17,875 & 23,875 & 1495 & 1728 & 1903 & 2283 \\... &... &... &... &... &... &... &... &... &... &... &... \\ \hline \hline \end{tabular}
\end{table} 
Table 8: AHP pairwise matrix of the indices of materials for the PPC case study. II to I7 refers to the seven selected material indices to rank materials, as defined in Section 3.2. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **I1** & **I2** & **I3** & **I4** & **I5** & **I6** & **I7** \\ \hline
**I1** & 1.00 & 0.20 & 0.20 & 0.14 & 0.50 & 0.20 & 0.20 \\
**I2** & 5.00 & 1.00 & 5.00 & 1.00 & 5.00 & 2.00 & 2.00 \\
**I3** & 5.00 & 0.20 & 1.00 & 0.20 & 1.00 & 0.50 & 0.50 \\
**I4** & 7.00 & 1.00 & 5.00 & 1.00 & 5.00 & 2.00 & 2.00 \\
**I5** & 2.00 & 0.20 & 1.00 & 0.20 & 1.00 & 1.00 & 1.00 \\
**I6** & 5.00 & 0.50 & 2.00 & 0.50 & 1.00 & 1.00 & 1.00 \\
**I7** & 5.00 & 0.50 & 2.00 & 0.50 & 1.00 & 1.00 & 1.00 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Weights of the material selection indices calculated for the case study. The best choices for the PPC application are Laserform 17-4 PH (heat treated) and LaserForm AlSi7 Mg0.6 (direct aging). Following the formalized path, compatible printers need to be selected according to product dimensions and batch size. As already pointed out, many machines are compatible with the application. Considering the main manufacturers, some machines are listed in Table 12 to confirm the compatibility with the product geometry.