HIGH-TEMPERATURE MECHANICAL PROPERTIES OF AlSi10Mg SPECIMENS FABRICATED BY ADDITIVE MANUFACTURING USING SELECTIVE LASER MELTING TECHNOLOGIES (AM-SLM)

Naor Elad Uzan ^1,2 Roni Z. Shneck ² Ori Yeheskel ¹ Nachum Frage ²

¹Department of Materials, Nuclear Research Center Negev, Beer-Sheva, Israel
²Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel

Development and applications of materials fabricated by AM using SLM technology requests in-depth investigation of a wide range of mechanical properties, including high temperature quasi-static mechanical and creep behaviors. In the present study mechanical properties (tensile strength and creep) of an AM-SLM AlSi10Mg alloy built in the Z-direction were investigated in the 25-400ºC temperature range. Specimens were tested after stress relief treatment. The results revealed that elastic modulus (E), yield stress (YS) and the ultimate tensile stress (UTS) values continuously decreased, while values of elongation rose with increasing temperature. The creep parameters, namely stress exponent n and apparent activation energy Q, were calculated based on the experimental data and found to be 25±2 and 146±26 kJ mol^-1, respectively. These values indicate that the creep mechanism at play is related to dislocation creep controlled by core diffusion. It was established that fine microstructure, which is responsible for the improved mechanical properties of AM-SLM AlSi10Mg parts, is also the cause of the poor creep resistance of this material.