Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 09, 2018 - September 12, 2018
Recently, the realization of the combination of selective laser melting (SLM) and high-strength aluminum alloys (Al alloys) has been discussed in mainly the aerospace industry. However, there have been several problems for the realization, and the one of serious problem is the occurrence of micro cracks in high-strength Al alloy objects fabricated by SLM. To solve the problem, some researchers have studied addition of alloying elements to high-strength Al alloy. In this study, we focused on the five percent Si additional A7075 Al alloy (A7075+5Si) and investigated the effects of the Si addition on the processability, microstructure, and mechanical properties. As a result, it was observed that the addition of Si element inhibited the formation of cracks in the A7075 objects. Our result suggests the high density and crack-free A7075+5Si objects had higher mechanical properties than the case of a conventional Al alloy: AlSi10Mg. However, the existing heat treatment (After solution treatment, water quenching and artificially ageing) did not increase the mechanical properties of 7075+5Si objects. In order to obtain the A7075+5Si objects with higher strength, it is required that the further studies about suitable heat treatment conditions for this alloy.
