Pdf am1

To learn more, view our Privacy Policy. To browse Academia. Log in with Facebook Log in with Google. Remember me on this computer. Enter the email address you signed up with and we'll email you a reset link. Need an account? Click here to sign up. Download Free PDF. A short summary of this paper. Download Download PDF. Translate PDF. Solidification and homogenization simulations are first carried out using a microsegregation model, before using the local compositions as an input for precipitation calculations, in order to characterize the influence of segregation on precipitation.

The chained microsegregation and precipitation simulations indicate that the global sequences of precipitation events remains are qualitatively the same at the different locations in the microstructure, but the growth and dissolution kinetics are strongly influenced by the local compositions.

Local supersaturations have a larger effect on the average radius of the precipitates than certain stages of the precipitation heat treatment. Another important feature of the Ni-based superalloys is Introduction the so-called cross-diffusion, which is the influence of the Ni-base superalloys are widely used for aeronautical concentration gradient of a given chemical species on the applications due to their outstanding mechanical flux of the other ones.

For all these reasons, numerical properties at elevated temperatures. This behavior is models are preferred to simulate the solidification and strongly dependent on the fraction and average size of the heat treatment of Ni-base superalloys. In the as-cast phase-field modelling is potentially the most accurate. The goal of this work is to study the effect of an using one-dimensional models such as DICTRA [3] or incomplete solution heat treatment on the spatial the pseudo-front tracking technique PFT [4, 5].

For this, microsegregation and precipitation ability to describe the influence of back diffusion on the models are applied to the industrial AM1 superalloy. Microsegregation can be simulated using analytical Precipitation can be modeled using methods based on models, such as the Scheil-Gulliver model or back- the evolution of the mean radius [] or by calculating diffusion models [1].

However, the dissolution of the the change of the particle size distribution PSD at each interdendritic eutectic and the evolution of composition time step []. The approaches based on the PSD are profiles in the primary phase during the solution heat generally more flexible when multicomponent alloys are treatment cannot be calculated with this approach. It The new average composition of the mixture domain and was shown that the model could describe the precipitation the temperature are used as inputs for equilibrium in the ternary Ni-Al-Cr system, showing good agreement calculations.

The outputs are the new local equilibrium with the experimental data of Booth-Morrison et al. In order to improve the computational composition heterogeneities associated with relatively efficiency of the model, the equilibrium calculations are short solution heat treatments is addressed through performed using an optimized coupling with Thermo- chained microsegregation and precipitation calculations.

Calc, which was described in details by Du and Jacot [5]. As for primary solidification, the mixture domain groups the interdendritic area and the diffusion coefficient of solute i with respect to primary phase embedded in the interface cell. The main effect of The value of Peut is a parameter of the model. Solidification terminates at Al was precipitate size distribution.

A Lagrangian approach is used. This approach differs from the so- interface. This can be explained by the decrease description has been described elsewhere [14]. As shown by the evolution of the The thermal history comprises several steps: solidification is described with a constant cooling rate of Analysis DTA [23].

The model predicts 0. Ageing was AM1 was also carried out as a reference. The simulations were compared with SEM X0- The total simulated times were 2.

In all cases, nucleation and growth of a which can be explained by the size distribution. The cumulative volume fractions were precipitates. They nucleation driving force more quickly.

The radii corresponding equilibrium values. This is due to the fact precipitate size distribution. Conclusions The second cooling is characterized by a second Numerical models have been developed to perform nucleation "burst", in which the total density increases chained simulations of microsegregation, homogenization dramatically. As the radius of the newly nucleated and precipitation in an industrial Ni-based superalloy.

Aaron, D. Fainstein, G. Rougier, A. Jacot, C. Gandin, P. Di Napoli, P. Ponsen, V. Jaquet, Acta Mater. The model was Gandin, P. Di Napoli, P. Ponsen, V. Jaquet, Acta Mater. The model was Booth-Morrison, J.

Weninger, C. Sudbrack, Z. The results Mao, R. Noebe, D. Seidman, Acta Mater. Jacot, M. Rappaz, Acta Mater. Grong, Acta Mater. The precipitation model was used to describe the [20] B.

Wilson, E. Cutler, G. Fuchs, Mat. Peyroutou, R. Tintiller, Internal report However, residual segregation [23] T. Grosdidier, A. Hazotte, A. Simon, Mat.

The importance of [24] F. Diologent, P. Caron, Mat. A, , , these two quantities for mechanical properties [22, 24] The approach developed here can be applied to other Ni-base superalloys, and can be used to study modified heat treatments, and the sensitivity of different alloys with respect to the processing conditions.

The authors are grateful to Prof. Michel Rappaz for fruitful discussions on this project. References [1] J. Dantzig, M. Warnken, D. Ma, A. Drevermann, R. Reed, S. Fries, I. Steinbach, Acta Mater. Walter, B.

Hallstedt, N. Warnken, Mat. A , , Gandin, A. Jacot, Acta Mater. Du, A. Langer, A. Schwartz, Phys. A, 21, , Lifshitz, V. Solids 19, 35, Kampmann, R. Decomposition of Alloys: The Early Stages. Oxford: Pergamon Press, , Perez, M. Dumont, D. Acta Mater.