PSI - Issue 34

Guilherme Guimarães et al. / Procedia Structural Integrity 34 (2021) 26–31 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

28

3

m ̇ [ − ] [K] [K] 1 1793 303

Table 1: Table of mechanical properties and plasticity model of 20MnCr5

A [MPa] B [MPa]

C

n

350

450

0.055 0.294 0914

The numerical model load case was configured restraining the sample bottom surface and applying a prescribed displacement at the sample top surface. By measuring the strain and the reaction force it was possible to co-relate the numerical model to the experiment. Every lattice configuration was submitted to a 10% strain, therefore it was possible to guarantee that the plastification was achieved. Figure 2 exemplifies the procedure.

Figure 2: Mesh to solid part conversion and numerical experiment.

2.3 Experimental Study The samples composed of 20MnCr5 were fabricated using a Laser Funde 200 selective laser melting (SLM) machine. The laser power was configured with 200w using an island scanning strategy with a 130 µm hatch spacing and an exposure time of 140 µs. The 20MnCr5 powder was deposited in 25 µm layers prior to each scanning procedure and the platform was held at 80°C during the manufacturing. It was manufactured a group of four specimens for each lattice configuration. The batch manufactured can be seen in Figure 3

Figure 3: Manufactured samples