Effect of Heat Treatment on the Microstructure and Mechanical Properties of a Composite Made of Al-Si-Cu-Mg Aluminum Alloy Reinforced with SiC Particles

In this paper, the effect of heat treatment (solution treatment and artificial aging) on the microstructure and properties of as-cast Al5Si1Cu0.5Mg aluminum alloy and its composite reinforced with 1.5 wt.% SiC particles was studied. The results showed that at 520 °C the optimal solution tim...

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Bibliographic Details
Main Authors: Xin Li, Hong Yan, Zhi-Wei Wang, Ning Li, Jian-Long Liu, Qiao Nie
Format: Article
Language:English
Published: MDPI AG 2019-11-01
Series:Metals
Subjects:
Online Access:https://www.mdpi.com/2075-4701/9/11/1205
Description
Summary:In this paper, the effect of heat treatment (solution treatment and artificial aging) on the microstructure and properties of as-cast Al5Si1Cu0.5Mg aluminum alloy and its composite reinforced with 1.5 wt.% SiC particles was studied. The results showed that at 520 &#176;C the optimal solution time for the aluminum alloy and its composite is 9 h and 6 h, respectively. After solution treatment, the microstructure of these two materials consists of a uniform distribution of nearly spherical eutectic Si and skeletal &#947; phase, furthermore, the composite eutectic Si phase is smaller and &#947; phase is more dispersed. After artificial aging at 175 &#176;C for 6 h, the microstructure of the composite is more dispersed and finer than that of the aluminum alloy on the whole and Al<sub>2</sub>Cu is precipitated. After heat treatment, the microhardness, ultimate tensile strength, and elongation of the aluminum alloy and its composite are higher than those of the as-casts. At the same time, the morphology of tensile fracture surface changes very much from a large area of cleavage plane to a large number of dimples and the tearing ridges become thicker for both the aluminum alloy and its composite.
ISSN:2075-4701