Phase-field modelling of magnetically induced microstructure evolution in martensitic polycrystals

马氏体多晶磁致微观结构演化的相场建模

• 批准号: 28422318
• 负责人: Professorin Dr. Britta Nestler
• 金额: --
• 依托单位: Institut für Angewandte Materialien - Mikrostruktur-Modellierung und Simulation (IAM-MMS)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/28422318?language=en
• 关键词: Phase; field; modelling; magnetically; induced

The magnetomechanical responses of magnetic shape memory (MSM) alloys to external magnetic fields are correlated with the coupled magneto-elastic domain structure evolutions in these materials. Hence, the kinetic pathways of the domain evolutions play a key role in determining the materials properties. Mesoscopic simulations based on phase-field modelling can provide valuable information to understand the dynamic processes and main quantities affecting the MSM effect. Therefore the aim of this project is to develop both, a new phase-field model and parallel 3D simulator for MSM alloys. The model formulation includes elastic, magnetic and elastomagnetic free energy contributions and different martensitic crystal structures. The thermodynamical data and free energies of the considered binary Fe-Pd and Fe-Pt and ternary Ni-Mn-Ga alloys needed to configurate the phase-field model will be exchanged from cooperating groups of the SPP 1239. The framework should be capable to describe the magnetic-field-induced evolution of polycystalline and polytwinned microstrüctures, of discontinuous structures with different twin boundaries and compositions, of the coupled process of grain growth (coarsening) and magnetically driven grain boundary motion, of grain- and twin-boundary diffusion and segregation patterns.

磁性形状记忆（MSM）合金对外磁场的磁力响应与材料中的磁弹畴结构演化耦合相关。因此，畴演化的动力学途径在决定材料性质方面起着关键作用。基于相场模型的介观模拟可以提供有价值的信息，以了解动态过程和影响MSM效应的主要量。因此，本项目的目的是开发一种新的相场模型和MSM合金的并行3D模拟器。该模型包括弹性，磁性和反磁性的自由能贡献和不同的马氏体晶体结构。所考虑的二元Fe-Pd和Fe-Pt以及三元Ni-Mn-Ga合金的化学数据和自由能将从SPP 1239的合作组中交换，所述合金需要配置相场模型。该框架应能够描述磁场诱导的多晶和多孪晶显微结构的演变，具有不同孪晶边界和成分的不连续结构，晶粒生长（粗化）和磁驱动晶界运动的耦合过程，晶粒和孪晶边界扩散和偏析模式。