Effect of alloying additions on threshold pressure for infiltration and porosity of aluminium-based melt infiltrated silicon carbide powder compacts

摘要

An instrumented heated pressure vessel has been used to determine the effect of alloying additions on the pressurised infiltration of SiC powder preforms by a series of Al-based melts in an air environment. The melts contained (wt/100) 3.4Mg, 5.0Ti, 2.5Cr, 6.0Cu, 3.8Si, 2.1Sr, 1.4Pb, or 0.8Ca as binary alloying additions to pure aluminium. Addition of up to 3.4 wt/100 Mg to pure Al reduced the threshold pressure slightly while Additions of 5.0/100Ti, 6.0/100Cu, 2.5/100Cr or 3.8/100Si did not affect threshold pressure Significantly.