Effect of impurity trappers on the distribution and removal of phosphorus from Si with Si-Cu solvent

Titanium (Ti) and calcium (Ca), as trappers, were introduced into copper-alloyed metallurgical grade silicon (MG-Si). The effects of trappers on the segregation behavior and removal efficiency of phosphorus (P) were investigated. It was found that P tended to enrich in the TiSi2 and CaCu2Si2 phases, and quenching above the eutectic temperature of Si-Cu alloy is conducive to the P removal. The corrosion process of the P-enriched phases indicated that Ca addition was in favour of P removal, while Ti addition was opposite. The results suggested that though the addition of Ti and Ca could effectively enrich P in the Si-Cu alloy, the acid sensitivity of P-enriched phases would affect the P removal.