Abstract
A semisolid slurry of 7075 aluminum alloy was prepared by means of a serpentine channel process (SCP) and rheo-diecasting. The influences of pouring temperature during slurry preparation, the injection pressure and die preheat temperature on the mechanical properties and microstructure of a rheo-diecast 7075 aluminum alloy were investigated. The results show that the as-cast strength and elongation of the tensile samples were 210–260 MPa and 0.2%–1.7%, respectively, with an injection pressure of 130 MPa, a pouring temperature of 700–720 °C, a preheat temperature of 280–350 °C, and a plunger speed of 0.5 ms−1. The results also show that the aged strength and elongation of the tensile samples were 420–453 MPa and 1.0%–1.4%, respectively, when the alloy solution was treated at 470 °C for 12 h and aged at 120 °C for 24 h. The substantial shrinkage porosity in the 7075 aluminum alloy tensile samples was the main cause of low elongation.
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Male, born in 1958, Ph.D, Professor. His research interests mainly focus on semi-solid processing of metallic materials. To date, he has published over 250 technical papers and two monographs.
This study was financially supported by the National Natural Science Foundation of China (Grant Nos. 50774007, 51771032 and 51701078), China Postdoctoral Science Foundation (Grant No. 2018M632846) and the Scientific Research Program of Hubei Provincial Education Department (Grant No. B2016053).
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Mao, Wm., Zhu, Wz. Tensile properties and microstructure of rheo-diecast 7075 alloy prepared by serpentine channel process. China Foundry 16, 161–167 (2019). https://doi.org/10.1007/s41230-019-8182-y
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DOI: https://doi.org/10.1007/s41230-019-8182-y