Wetting of porous titanium carbonitride by Al-Mg-Si alloys

Wetting of porous TiCo0.17N0.83 by Six alloys from the Al-Mg-Si system (pure Al, pure Mg, Al-15 at.% Mg, Al-10 at.% Si, Mg-5 at.% Si, and Al-10 at.% Mg-10 at.% Si) in an argon atmosphere was studied using the sessile drop experiment. The contact angle of the liquid drops on TiCo0.17N0.83 substrates was measured as a function of temperature. Aluminium, Al-10 at.% Si, and Al-10 at.% Mg-10 at.% Si did not wet TiC0.17N0.83 in the studied temperature range. Magnesium always wetted TiC0.17M0.83 with a minimum contact angle of approximate to 44 degrees at 900 degrees C, and alloying with Mg significantly lowered the contact angle of Al on TiCN. Alloying with Si deteriorated the wetting of TiCN by Mg. A comparative study between the systems was conducted, based on the results and on data available in the literature. The improvement of the wetting of TiCN by Al due to alloying with Mg can be explained by the segregation of Mg to the interface with TiCN. where it lowers the interface energy. The addition of Si to pure Mg or to Al-Mg results in an increase in the contact angle on TiCN. (C) 1999 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.