不对称温变形粗晶Fe-Si合金中的剪切带和择优取向行为机理

Silicon steel is one of the necessary and key materials in power, electronic and defense industry.However, traditional technology restricts severely the increase of production efficiency and potential performance, owing to complicated control,long flow path, low yield and high cost.The green and short process technology of high yield, low energy consumption and high efficiency become an important development direction of the new generation of high performance silicon steel.Recent studies show that the in-grain shear band formation of coarse grained silicon steel can greatly promote the development of favorable textures (such as Goss or Cube),which show a distinct advantage in producing the silicon steels with high magnetic induction and low iron loss. Based on the coarse grained silicon steel obtained by strip casting, the influence of micro-strain mechanism, matrix orientation difference, inhomogeneous stored energy on shear band formation will be investigated in this project. Under the asymmetrical warm rolling, the theory on recrystallization behaviors of Fe-Si alloy such as nucleation, growth and crystallographic orientation, will be proposed, to control the microstructure and texture over the whole process without hot rolling and normalizing. The relationship between microstructure, texture, magnetic properties and precipitation in an ultra-short technologic route will be revealed. The aim of this investigation is to make a breakthrough in the manufacturing theoretical of non-oriented and oriented silicon steels, and then, propose a new physical metallurgy theory to develop high performance electrical steels, which has important scientific significance and practical value.

硅钢是电力、电子和国防领域不可或缺的关键材料。传统硅钢存在工艺复杂、流程冗长、可加工性能差、成材率低和制造成本高等瓶颈问题，大大限制了生产效率的提高和性能潜力的挖掘。因此，开发高成材率、低能耗、高效率的绿色化短流程生产技术，成为新一代硅钢的重要发展方向。最近研究表明，粗晶硅钢晶内剪切带的生成可以大大促进有利织构（如Goss或Cube）的发展，在开发高磁感低铁损电工钢方面具有显著的优势。本项目以薄带连铸的粗晶硅钢带为对象，揭示剪切带生成与微观应变机制、基体取向差异、储能不均匀性之间的相互关系，研究不对称温变形条件下再结晶形核、长大和取向行为的基础理论、影响因素和控制方法，实现无热轧常化下微结构的精确设计与调控，探索超短流程硅钢组织、织构和磁性能一体化控制理论与技术。本研究旨在突破传统硅钢制造的理论框架，为高性能高效率电工钢开发提供新的基础理论支撑，具有重要的科学意义和实际应用价值。

无常化温轧生产Fe-3%Si钢带的方法是一种具潜力的一项新技术，本项目研究了Fe-Si合金在温轧前后、析出物，显微组织、剪切带和织构等演变的基础理论，阐明了温轧硅钢的剪切带生成、取向差异、储能不均匀性之间的相互关系，研究不对称温变形条件下再结晶形核、长大和取向行为的基础理论、影响因素和控制方法，实现无热轧常化下微结构的精确设计与调控，探索短流程硅钢组织、织构和磁性能一体化控制理论与技术。研究获得以下重要结果：（1）温轧组织和织构的形成机制，适当增加异速比和温轧温度有利于Goss织构生成；（2）异步轧制Σ3等特殊晶界演变规律及影响因素。（3）温轧工艺对抑制剂的形貌和尺寸的影响；（4）不同温轧温度下，典型织构主要为α织构和γ织构。随着温度的升高，α织构强度减少，而γ织构的强度增加，η织构基本上变化不大。（5）随着温轧温度的提高，取向硅钢成品板铁损值逐渐增加，磁感值先增加后减小，在200℃温轧材料的磁性能最优，磁感应强度和铁损分别为B8=1.780T，P1.7/50=3.229W/Kg。在国内外期刊或学术会议上发表高水平论文14篇，其中SCI 收录7 篇，EI 收录1篇，参加国内外学术交流共4人次，培养硕士4名（毕业2名，在读2名）。上述研究成果为生产高性能取向电工钢提供了理论基础和技术途径。