基于我们在非晶合金的制备和性能研究的工作基础，申请者提出以低玻璃转变温度（Tg）的软磁性铁基Fe-P-C三元非晶合金为基础合金，通过多元合金化，在维持其低Tg的同时，提高过冷液体热稳定性和玻璃形成能力，研制超塑性加工用软磁性铁基非晶合金的设想。系统研究两组（Fe，Co，Ni）、（P，C，B，Si）相似元素和微量大原子径过渡金属元素添加对基础非晶合金热稳定性、玻璃形成能力以及磁性的影响规律，建立Tg、过冷液相区间、非晶形成临界尺寸及磁性与合金成分的关联。优化合金成分，制备出超塑性加工用铁基多元块体非晶合金，并澄清合金元素影响过冷液体稳定性的机理。研究铁基多元非晶在过冷液相区的变形行为，阐明其变形机制。结合结构和性能表征，研究过冷液相区变形工艺参量对合金磁性、力学性能以及微结构的影响规律，揭示变形后非晶合金的性能与结构的相关性。为发展超塑性加工用软磁性铁基非晶合金提供理论依据和工艺技术支撑。

Based on our previous studies of bulk metallic glasses and their functional properties, a proposal is put forward for development of soft magnetic Fe-based metallic glasses having low glass transition temperatures (Tg), highly stable undercooled liquid states and large glass-forming abilities for superplastic processing. These multicomponent alloys are fabricated by alloying the basic Fe-P-C system. The alloying effects of two categories of like elements, namely, ( Fe, Co, Ni) and (P, C, B, Si), and large atomic size transition metal minor-alloying elements on the thermal stability, glass-forming ability and magnetic properties of Fe-P-C alloys will be systematically studied. The compositional dependences of Tg, the supercooled liquid region, critical glass-forming diameter, and magnetic properties are to be revealed in these alloys. Fe-based bulk metallic glasses applicable for superplastic processing are eventually determined by composition optimization. The underlying stability mechanisms of their supercooled liquids are to be clarified, followed by a study of the deformation behaviors in the supercooled liquid region along with the superplastic deformation mechanisms. The structure-property relations in deformed alloys will be established through a comprehensive investigation of the influences of superplastic processing parameters on their microstructure, mechanical properties and magnetic properties, which serve as the theoretical guiding principles for practical superplastic processing of soft magnetic Fe-based metallic glasses.