Thermodynamic Analysis of the Ta-W-C and the Ta-W-C-N Systems

摘要

A new thermodynamic analysis of the Ta W-C system is presented based on the211u001eexperimental work by Rudy1 and Rudy et al2.. The Gibbs energy functions of the 211u001efollowing phases were determined: the liquid phase or (Ta,W) (C,N)x carbonitride 211u001e(cF8), and the hcp phase or (TaW)2(CN)x carbonitride (hP3). Calculated phase 211u001eequilibria are compared with experimental data. The new thermodynamic description 211u001eof the ternary Ta-W-C system is combined with assessments/predictions of the Ta-W-211u001eN, Ta-C-N and W-C-N systems and equilibria in the quaternary Ta-W-C-N system are 211u001ecalculated. Calculated phase diagrams of all the relevant binary systems are 211u001epresented.