Dendritic solidification in a Fe-0.11C wt% steel

This computer simulation of dendritic solidification been provided by courtesy of V. Pavlik and U. Dilthey of the ISF-Welding Institute of Aachen University in Germany. The solidification simulations use a technique called "cellular automata" in combination with finite difference methods. Cellular automata allow non-trivial processes and patterns to be computed starting with simple deterministic rules. Solute concentration contours in the parent phase are represented by colours. Look out for the development of secondary dendrite arms, coarsening of these arms, the development of solute segregation due to non-equilibrium solidification. Note how the microstructure changes radically as a function of the solidification parameters (velocity and temperature gradient)

Dendritic solidification in Fe-0.11 wt% C velocity 10 mm/s, temperature gradient 100 K/mm. Have a careful look at the development of the secondary dendrite arms. The initial spacing between the secondary dendrite arms is much finer than in the final microstructure. This is because of coarsening - some of the finer arms dissolve as the coarser ones grow. The later stages also show the coalescence of the dedrite arms (both primary and secondary).

More details on

http://www.msm.cam.ac.uk/phase-trans/dendrites.html

Category:

Education

Tags:

• solidification
• dendrites
• simulation
• cellular automata
• finite difference