PSI - Issue 8

Author name / Structural Integrity Procedia 00 (2017) 000–000

P. Conti et al. / Procedia Structural Integrity 8 (2018) 410–421

417

Tab.II – Results of the finite elements analyses Analyses plan

Results

Conductivity level ( ݇ ) × 0.9

Specific heat level ( ܥ ݌ ) × 0.9

Young’s modulus ܧ × 0.9 × 1.1

Test number

Max. Temp [°K]

Max. Stress (diag.) [MPa]

1 2 3 4 5 6 7 8

2890 2890 2813 2813 2527 2527 2459 2459

880

× 0.9 × 0.9 × 0.9 × 1.1 × 1.1 × 1.1 × 1.1

× 0.9 × 1.1 × 1.1 × 0.9 × 0.9 × 1.1 × 1.1

1075

× 0.9 × 1.1 × 0.9 × 1.1 × 0.9 × 1.1

864

1056

824

1008

828

1012

Fig. 9a – Test no.1 – Temperature pattern (all the model)

Fig. 9b – Stress pattern (all the model)

Fig.10a – Test no.1. Temperature pattern (only scan island)

Fig.10b – Test no.1. Stress pattern (only scan island)

The data were analyzed with DOE techniques to verify the influence of the physical parameters on the process performances. Two performance features were considered; the first one is the maximum temperature in the scanned island: it is a clue of the complete melting of the layer. The second one is the maximum stress along the diagonal (down-left/top right). It was chosen, instead of the absolute maximum stress, because of some non-meaningful stress concentrations around the non-melted pixels that could bias the result. The complete results are displayed in Tab. II, right side. As one can see, the maximum temperature are identical for every couple of tests; it is an expected result as the only difference between the parameters set is the Young’s modulus which does not affect the thermal behaviour.