纳米MgAl2O4增强铁基合金低温原位合成及成相机制

项目名称： 纳米MgAl2O4增强铁基合金低温原位合成及成相机制

项目编号： No.51501101

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 一般工业技术

项目作者： 戴雷

作者单位： 三峡大学

项目金额： 20万元

中文摘要： 增强相的热稳定性及其制备成本很大程度上限制了纳米增强铁基合金（Nano-phase Strengthened Fe-based Alloys）的推广和使用，引入高热稳定的MgAl2O4纳米增强相是解决该问题的有效途径之一。由于外加增强相存在污染、成本等问题，原位合成纳米MgAl2O4增强相成为新的选择。本项目围绕低温原位合成纳米MgAl2O4增强铁基合金开展工作，对其显微组织、成相过程和动力学进行系统分析，其目标是在铁基合金基体基础上，以廉价的MgO、Al2O3为添加物，经机械球磨和热压烧结低温原位合成MgAl2O4增强铁基合金，主要研究MgAl2O4增强相形成机制及其对门槛应力、屈服强度的影响规律，阐明增强相特征、工艺参数与组织和性能之间的作用本质，探索实现组织控制新方法。本项目可有效解决纳米增强铁基合金中增强相稳定性不足和分布不均匀难题，为同类材料组织控制提供理论指导和实验依据。

中文关键词： 原位合成；成相机制；纳米增强；MgAl2O4增强相；铁基合金

英文摘要： The problems existing in the reinforcement of Nano-phase Strengthened Fe-based Alloys are thermal stability and excessive costs, which constrains their promotion and application. The introduction of high thermal stability MgAl2O4 reinforcement is one of the effective ways to solve these problems. It is a new choice to adapt the in-situ synthesis technology to prepare MgAl2O4 reinforcement due to the pollution and high-cost when adding MgAl2O4 directly. Taking the in-situ synthesized MgAl2O4 reinforced Fe-based alloy at low temperature as research object, the project intend to perform systematically analyzing on microstructure evolution, formation process and kinetics of phase transformation. Based on the Fe-based alloy matrix, we intend to use the low-cost MgO and Al2O3 powders as the additive to in-situ fabricate novel MgAl2O4 strengthened Fe-based alloy by mechanical milling and hot pressing. This proposal mainly to study the formation process and mechanism of MgAl2O4 reinforcement and their influence law on the threshold stress and yield strength, microstructure evolution and kinetics mechanism of phase transformation in sintering process, to reveal the law between the characteristics of MgAl2O4 reinforcement, process parameters and microstructure and properties, to explore a new method of microstructural control in Fe-based alloy. This proposal will effectively solve the stability and heterogeneous dilemma of the reinforcement in Fe-based alloy and provide theoretical and experimental basis for microstructural control of analogous materials.

英文关键词： in-situ fabrication ; phase transformation mechanism;nano-phase strengthened ;MgAl2O4 reinforcement; Fe-based alloy