Zr-Co-Al(-M)非晶基复合材料的组织与力学性能调控及塑韧化机理

针对Zr-Co-Al系块体非晶合金（BMG）变形过程中的室温脆性和应变软化问题，本项目拟以Zr56Co28Al16非晶合金为基础，协同成分调控、引入内生晶相、相变诱导塑性（TRIP）等手段提高合金的加工硬化能力和塑韧性。采用高通量制备与表征及水冷铜模吸铸等技术，系统研究成分对Zr-Co-Al(-M)（M为Ag、Y等）合金玻璃形成能力（GFA）、内禀特性、组织结构和力学性能的影响，优选合金成分，制备大尺寸高强度BMG；通过快速退火引入内生B2相形成非晶基复合材料，研究内生相特征（尺寸、数量与分布）和材料力学性能的调控机制；结合形变诱导B2相马氏体相变的TRIP效应，进一步提升复合材料的加工硬化能力和塑韧性，深入研究其协同变形与塑韧化机理。本项目的实施既可丰富BMG的塑韧化理论体系，又可为高强高韧Zr-Co-Al(-M)非晶基复合材料的制备提供理论指导和实验依据，促进其实际应用与推广。

In order to make up the shortcomings of room temperature brittleness and strain softening during the deformation of Zr-Co-Al bulk metallic glass (BMG), several approaches, such as alloying component regulation, in-situ crystallites formation and phase transformation-induced plasticity (TRIP), will be synergistically used to enhance the work-hardening ability, plasticity and toughness of the materials based on Zr56Co28Al16 amorphous alloy. Zr-Co-Al(-M) (M is Ag and Y etc.) alloys will be prepared by using high-throughput method and water-cooled copper mould suction casting technology, and the effects of the alloying components on the glass-forming ability (GFA), intrinsic properties, microstructure and mechanical properties of the alloys will be systematically studied to understand their relationship. BMGs with big diameter and high strength will be prepared after optimizing alloying component. On this basis, the in-situ B2 crystallites will be introduced into BMGs to get BMG matrix composites by using flash annealing technology, and the characteristics (size, quantity and distribution) of B2 phase and mechanical properties of the composites will be regulated by adjusting the technological parameters. In order to further improve the work-hardening ability and ductility of these BMG composites, we will introduce TRIP effect associated with deformation-induced martensite transformation (DIMT) of in-situ B2 crystallites by deformation at room temperature. At last, the mechanisms of cooperative deformation and ductilization of the composites will be investigated intensively. This work will not only enrich the academic system of BMG ductilization, but also provide theoretical and experimental guidance for the fabrication and application of Zr-Co-Al(-M) BMG composites with high strength and toughness.