微纳米尺度第二相调控阻尼NiTi记忆合金及其相变和阻尼行为

项目名称： 微纳米尺度第二相调控阻尼NiTi记忆合金及其相变和阻尼行为

项目编号： No.50871039

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 张新平

作者单位： 华南理工大学

项目金额： 36万元

中文摘要： 采用微纳米尺度、高本征阻尼低密度第二相对NiTi记忆合金阻尼和力学性能进行调控，并用于轻质、高强和高可靠性智能阻尼结构及器件的制造，具有非常重要的科学研究价值和良好的工程应用前景。本项目采用粉末冶金方法制备出以NiTi合金为基体，以高本征阻尼、低密度、微纳米尺寸颗粒添加相或熔渗相调控阻尼和强度的新型轻质、高强度复合阻尼材料，并形成了系统的材料制备理论及获得了关键制备技术；采用相场法模拟研究了NiTi形状记忆合金中Ni4Ti3的共格析出行为，对其长大动力学和分布形态进行准确描述和模拟再现，并研究其对马氏体相变过程和超弹性变形能力影响的规律；研究了NiTi合金基复合材料的相变和超弹性变形行为，揭示了不同调控相含量和分布特性对材料力学和阻尼性能影响的规律，建立了力学性能和阻尼能力与第二相特征之间的定量相关性；全面认识并阐明了NiTi合金基复合材料中多阻尼机制叠加或耦合原理。本项目的研究成果把NiTi合金基复合材料的优化制备技术、相变和超弹性特性及阻尼行为方面的基本认识向前推进了一大步，可为新型高阻尼材料的设计和制备提供理论指导，并为其在轻质、高强智能阻尼器件和结构方面的应用奠定了理论基础。

中文关键词： NiTi形状记忆合金；阻尼；微纳米尺度；第二相调控；相变

英文摘要： This project aims to develop NiTi memory alloy based damping materials engineered with micro/nano- scale second phases which possess excellent properties of high intrinsic damping capacity and low density, and to employ the materials for manufacturing lightweight, high strength, intelligent damping structures and devices with high reliability. The project is of great significance in both fundamental research and engineering application. The study has been focused on: 1) fabricating lightweight and high strength multiphase damping materials which consist of NiTi based alloy and micro/nano-meter sized particles or second phases with low density and high intrinsic damping capacity, by means of powder metallurgy process and pressureless metal infiltration method; and developing systematic theories of materials systhesis and acquiring key technologies on materials fabrication; 2) showing the microstructure evolution and growth kinetics of Ni4Ti3 precipitates in NiTi alloys by the phase field method, and further revealing the influential law of the precipitates on the martensitic transformation behavior and the superelasticity of NiTi shape memory alloys; 3) studying systematically the phase transformation and superelastic deformation behavior of NiTi alloy based multiphase composites; characterizing the influences of different addition amounts of the engineered phases and their distribution on mechanical properties and damping capacity of the NiTi based composites; and establishing a quantitative correlation between damping capacity/mechanical properties of the alloys and the feature of the engineered phases; 4) understanding fully the superposition or coupling principle of multiple damping mechanisms in the NiTi based composites. The outcomes obtained from the present project have pushed forward the fundamental understanding on the material optimization fabrication theory of NiTi based composites, phase transformation and superelasticity as well as damping behaviors of the composites. These results are expected to provide theoretical guide for design and fabrication of new high damping materials, and offer a theoretical framework underpinning the application of high damping and high strength NiTi based composites for lightweight, intelligent damping devices and structures.

英文关键词： NiTi shape memory alloys; Damping; Micro/nano- scale; Engineered second phase; Phase transformation