Primary silicon formation in hypereutectic alloy Al – 16.5% wt. Si treated in the liquid state by a changing unipolar pulsed electric current

Structure formation during the crystallization of a melt Al – 16.5% wt. Si treated with packages of unipolar electrical pulses of various frequencies and amplitudes have been studied. Grinding of primary silicon crystals was observed, the size and morphology of which depend on the electric current density. DTA showed a significant change in the parameters of both melting and solidification processes. X-ray diffraction studies have established the formation of additional silicon phases: polytype silicon, and silicon with tetragonal and bcc structures. The results obtained are explained by the transformation of the structure and a decrease in the degree of micro inhomogeneity of the Al-Si melt a change in the short-range order of Si-Si atoms.