OpenPhase example

Tempered Martensite

Keywords

Superalloys Dislocations Rafting Crystal plasticity Phase-field method

Determine martensite start and finish dependent on the quenching rate.
Tailor amount and distribution of carbides.
Optimize the heat treatment for each specific steel grade.
Determine flow curves of tempered martensite.
Trace all relevant microstructural features during processing and service.

Mechanical properties of steel vary dependent on the heat treatment process. An exceptional examples is tempered martensite where the mechanical properties can be tuned from for high hardness, high strength, wear resistance, and corrosion resistance of the martensitic structure to good ductility and toughness of almost ferritic structure with precipitated carbides. Simulating the evolution of the microstructure "from quenching to fracture" enables you to tailor your process to the required mechanical properties appropriate to the intended use. which prevents gamma prime from merging.

OpenPhase capabilities

Martensite start is predicted based on driving forces to transformation using alloy thermodynamics
Martensite finish is determined by transformation kinetics
Internal heat release due to transformation is considered
Results are transformed to virtual dilatometer curves

Multiple modules for carbide nucleation (random statistics, dedicated sites, interfaces, junctions, local residual strain)
Growth stage based on local carbon supersaturation and tetragonal distortion relaxation
Ripening stage determined by multi-component diffusion and solute element cross-interaction
Consideration of lattice strain effects on diffusion, coherency strain, and coherency loss during growth

Investigate system response to different heat extraction conditions
Tailor heat extraction through inverse optimization
Test nucleation conditions of various carbide populations and competitive growth
Investigate microalloying effects on precipitation and mechanical stability

Optimize crystal plasticity models with sparse experimental input
Interpolate and extrapolate flow rules for FE analysis at sample scale
Determine rules as a function of local alloy composition
Tailor heat treatment process for optimized mechanical response

Automatically monitor size and distribution of all microstructural elements
Apply autocorrelation functions for application-specific materials characteristics
Provide 3-D information for correlation with 2-D experimental micrographs