Novel Mixed-Mode Phase Transition Involving a Composition-Dependent Displacive Component

S. Nag, A. Devaraj, R. Srinivasan, R. E. A. Williams, N. Gupta, G. B. Viswanathan, J. S. Tiley, S. Banerjee, S. G. Srinivasan, H. L. Fraser, and R. Banerjee

Phys. Rev. Lett. 106, 245701 – Published 17 June 2011

Abstract

Solid-solid displacive, structural phase transformations typically undergo a discrete structural change from a parent to a product phase. Coupling electron microscopy, three-dimensional atom probe, and first-principles computations, we present the first direct evidence of a novel mechanism for a coupled diffusional-displacive transformation in titanium-molybdenum alloys wherein the displacive component in the product phase changes continuously with changing composition. These results have implications for other transformations and cannot be explained by conventional theories.

Received 8 March 2011

DOI:https://doi.org/10.1103/PhysRevLett.106.245701

Authors & Affiliations

S. Nag^1,2, A. Devaraj¹, R. Srinivasan³, R. E. A. Williams^4,5, N. Gupta¹, G. B. Viswanathan⁶, J. S. Tiley⁶, S. Banerjee⁷, S. G. Srinivasan^1,*, H. L. Fraser^4,5, and R. Banerjee^1,2,†

¹Department of Materials Science and Engineering, University of North Texas, Denton, Texas 76203, USA
²Center for Advanced Research and Technology, University of North Texas, Denton, Texas 76203, USA
³ExxonMobil Research and Engineering Company, Annandale, New Jersey 08801, USA
⁴Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210, USA
⁵Center for Accelerated Maturation of Materials, The Ohio State University, Columbus, Ohio 43210, USA
⁶Materials and Manufacturing Directorate, Air Force Research Laboratory, Dayton, Ohio 45433, USA
⁷Department of Atomic Energy and Atomic Energy Commission, Mumbai, India