Computer Simulation of Martensite Spread: A Stochastic Approach

In bulk polycrystalline materials, the first nucleation event of a martensite plate within a single grain may induce transformation in one or more neighboring grains, resulting in a cluster of partially transformed grains: ‘the spread event’. The collection of these single spread events can be defined as the ‘spread’ or ‘martensite spread’. First, in this paper, martensite spreads are analyzed to estimate the mean number of partially transformed grains in a single spread event. Secondly, taking the quantitative knowledge gained from this analysis as a starting point, a computer simulation of the martensite spread is proposed. This computer simulation is carried out in a 3-d network of space-filling grains represented as Kelvin polyhedra and is based on a stochastic approach. The experimental and simulation results are presented, compared and discussed. We conclude that the stochastic computer simulation of martensite spread could successfully describe important quantitative aspects of martensite spread.