Wetting Properties of W by Molten SiO2-MgO-Al2O3 Ternary Eutectic Composition

The contact angle θ of the melt with the SiO2-MgO-Al2O3 ternary eutectic composition on W substrates and the penetrating behavior of the melt into W powder compacts were studied in the temperature range from 1350° to 1650°C in N2/H2 atmosphere. θ decreased with increasing temperature and θ in a wet H2 atmosphere was about 20° smaller than that in the dry H2 atmosphere. No time dependence of θ or no reaction between the melt and W was observed at 1600°C. The shrinkage of W compacts after the penetration of the melt was observed when θ was below 40°.