High temperature mechanical integrity of selective laser melted alloy 718 evaluated by slow strain rate tests

Strain rate dependent deformation behaviours of selective laser melted Alloy 718 (IN718) are systematically studied at 550 and 650 °C by slow strain testing, with a forged counterpart as reference. Selective IN718 shows significant susceptibility to intergranular cavitation, resulting in ductility degradation decreasing rate. Detailed fractography cross section inspections employed identify the damage mechanisms. Creep rates also estimated compared conventional counterparts. The possible critical factors for inferiority time resistance discussed.