2.1. Equipment and Materials

The SLM specimens are made on EOS M280 equipment (manufactured by the German Company EOS, Freiberg, Germany), which is equipped with a Yb-fibre 400 W laser with a focal spot diameter of 100 µm. The maximum scanning speed and layer thickness distribution are 7000 mm/s and 20–50 µm, respectively. The maximum building volume (W × D × H) is 250 mm × 250 mm × 325 mm. The build chamber was flown with argon to avoid oxidation and nitriding of liquid metal in molten pool and the density of specimens can be achieved above 98%. EOS Titanium Ti-6Al-4V (a titanium alloy powder) was used and average size of the powder particles was 45 µm with an apparent density of 4.41 g/cm³; the nominal composition of the gas atomized powder was Ti (85.7 wt %), Al (6.75 wt %), V (4.5 wt %), the ingredients (balance).