|About this Abstract
||Materials Science & Technology 2012
||Raymond W. Buckman, Jr. Memorial Symposium for Refractory Metals and Alloys
||Thermodynamic Modeling of the Mo-Hf-C System and Simulation of Precipitate Evolution in Mo-2Hf-0.2C Alloy
||Erwin Povoden-Karadeniz, Ernst Kozeschnik
|On-Site Speaker (Planned)
Using the CALPHAD approach, the thermal stabilities of (Hf,Mo)C and (Mo,Hf)2C solid solutions are determined, and the effect of Hf on the solubility of carbon in Mo is evaluated. The assessed thermodynamic model parameters are used for the evaluation of chemical potentials and driving forces, which are needed in the precipitation kinetics evolution equations. The interfacial energy between matrix and precipitates is calculated using the generalized broken-bond model. Number densities, radii and volume fractions of (Hf,Mo)C and (Mo,Hf)2C particles in heat treated Mo-2Hf-0.2C (wt. %) alloy are predicted, which are essential for the mechanical properties, in particular high-temperature strength. Further elements can be implemented in the thermodynamic Mo-Hf-C database in order to simulate precipitation evolution of multi-component heat treatable Mo-base alloys.
||Definite: A CD-only volume