1. Influence of a Zn Interlayer on the Interfacial Microstructures and Mechanical Properties of Arc-Sprayed Al/AZ91D Bimetals Manufactured by the Solid-Liquid Compound Casting Process.
- Author
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He K, Zhao J, Cheng J, Shangguan J, Wen F, and Wang Y
- Abstract
A novel technique combining solid-liquid compound casting (SLCC) with arc spraying was designed to manufacture the arc-sprayed Al/AZ91D bimetals with a Zn interlayer. The Al/Mg bimetal was produced by pouring the AZ91D melt into the molds sprayed with Al/Zn double-deck coating, during which the arc-sprayed Zn coating acted as the interlayer. The effect of the Zn interlayer on microstructures, properties, and fracture behaviors of arc-sprayed Al/AZ91D bimetals by SLCC was investigated and discussed in this study. The optimal process parameter was acquired by analyzing the results from different combinations between the arc-spraying time of the Zn coating (10, 18, and 30 s) and the preheat time of the Al/Zn double-deck coating (6 and 12 h). The interfacial microstructures of the arc-sprayed Al/AZ91D bimetals with a Zn interlayer could be approximately divided into two categories: One was mainly composed of ( α -Mg + Al
5 Mg11 Zn4 ) and ( α -Al + Mg32 (Al, Zn)49 ) structures, and the other primarily consisted of ( α -Mg + Al5 Mg11 Zn4 ), (MgZn2 (main) + β-Zn), and (β-Zn (main) + MgZn2 ) structures. In the interface zone, the ( α -Mg + Al5 Mg11 Zn4 ) structure was the most abundant structure, and the MgZn2 intermetallic compound had the highest microhardness of 327 HV. When the arc-spraying time of the Zn coating was 30 s and the preheat time of the Al/Zn double-deck coating was 6 h, the shear strength of the arc-sprayed Al/AZ91D bimetal reached 31.73 MPa. Most rupture of the arc-sprayed Al/AZ91D bimetals with a Zn interlayer occurred at the ( α -Mg + Al5 Mg11 Zn4 ) structure and presented some typical features of brittle fracture., Competing Interests: The authors declare no conflict of interest.- Published
- 2019
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