Formation Mechanisms and Microstructure Characterization of Al/Al3Ni In-situ Composite by Compound Casting

The Compound casting method was used to produce an Al/Ni bimetal composite. The mechanisms of formation of the reinforcing intermetallic phases were studied and the produced bimetal composite's microstructure was then characterized. The results showed that the Al/Ni interface consisted of two intermetallic layers including Al3Ni2 and Al3Ni. It is suggested that the Al3Ni reinforcing particles of the composite originated from two sources. (1) Some Al3Ni particles detached from the Al3Ni layer formed at the interface between the Ni core and the Al melt and dispersed in the liquid Al and (2) Al-Al3Ni eutectic phase, which formed during the solidification process. The increase in the temperature led to the formation of more reinforcing particles and extended the depth of dispersion of the particles in the Al matrix. (C) The Minerals, Metals & Materials Society and ASM International 2019