 W. Craig Carter

W. Craig Carter is a materials scientist at MIT whose research applies physical analysis and computation to the evolution of microstructure. His departmental profile identifies work on material properties, phase transitions, fracture and battery-electrode materials.^[ref]

MIT's official course page identifies him as the instructor of its Fall2002 Thermodynamics of Materials course. The associated Unstable Solutions: MIT 3.00 Lecture 32 by W. C. Carter prints the byline W.C.Carter and develops the regular solution model, common-tangent construction and instability toward phase separation.^[ref]

An original dimensionless version of the regular solution model makes one teaching point explicit. Let $x$ be mole fraction andIts curvature isAt equal composition $x=1/2$, this becomes $4-2\chi$. For stipulated $\chi =3$, the value is $-2$. A small symmetric split of composition into $x\pm \delta$ changes the average free energy by $\frac{1}{2}{g}^{\prime \prime }(x){\delta }^2$ to leading order, which is negative here. The homogeneous state can therefore lower this model free energy through small composition fluctuations. This illustrates spinodal decomposition; it is a derivation in a chosen parameter convention, not a measurement of a named alloy.

The common-tangent construction separately determines equilibrium coexistence compositions. Carter's notes use these geometrical and thermodynamic conditions to distinguish stability questions from the eventual separated phases. His MIT faculty profile provides an institutional portrait.