Papers by Author: Christian Lexcellent

Abstract: Classically a master curve as Dorn's equation is applied for elucidating stationary creep behaviour within high temperature range (T > 0.6 Tm). As the diffusion of both 63Ni and 44Ti have been measured in an equiatomic NiTi, an effective choice of creep-relevant diffusion coefficient D may be possible. Moreover, creep measurements in the same temperature range performed can be found in the literature. The correlation does not permit to establish precisely what D coefficient to integrate in the Dorn's equation.

Abstract: At first, some comments are made concerning the capacity of prediction of the microstructure for shape memory alloys by the Crystallographical Theory of Martensite. Secondly, the basic foundations of the phenomenological modeling of shape memory alloys behavior at the macroscopic scale are given. A special attention is devoted to the yield surface of phase transformation initiation in the stress space and its convex dual: the set of effective transformation strains in the strain space.