Features of the surface structure of Al-Cu alloys before and after reaction with the liquid Ga-In eutectic

The structural, morphological, and chemical characteristics of aluminum-copper alloys before and after contact with the liquid Ga-In eutectic have been studied. X-ray diffraction (XRD) analysis has revealed that alloying results in the formation of Al9Cu11.5 and Al2Cu intermetallic compounds and CuAl0.005, CuAl0.14, and AlCu0.004 substitutional solid solutions. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) have shown that, for the CuAl0.005 and CuAl0.14 substitutional solid solutions of aluminum in copper and the individual Al9Cu11.5 intermetallic compound in contact with the liquid Ga-In eutectic, surface spreading of the eutectic without any significant morphological and chemical changes in the studied systems is observed. At the same time, the alloy containing the Al2Cu intermetallic compound and the phase of the AlCu0.004 substitutional solid solution of copper in aluminum interacts with liquid Ga-In eutectic owing to the activation of aluminum as a solid solution component. This activated Al-Cu alloy reacts with liquid tert-butyl chloride in the presence of ethylene to form catalyst Al-Cu-Cl complexes in situ. It has been speculated that these complexes are mostly formed owing to the dissolution of the phase of the AlCu0.004 substitutional solid solution of copper in aluminum in a medium of liquid tert-butyl chloride.