粉末固结法制备纳米结构和超细结构块体金属材料过程中颗粒界面转化的研究

项目名称： 粉末固结法制备纳米结构和超细结构块体金属材料过程中颗粒界面转化的研究

项目编号： No.51271115

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 一般工业技术

项目作者： 张德良

作者单位： 上海交通大学

项目金额： 80万元

中文摘要： 未转化颗粒界面和颗粒界面孔洞对用粉末固结法制备的纳米结构和超细结构块体材料的机械性能和物理性能有着严重的负面影响也掩盖了这类材料的潜在的优异性能。现在人们还无法准确地确定即能保证颗粒界面完全转化又能严格限制晶粒长大的粉末固结工艺手段和条件，从而严重限制了粉末固结法在制备大尺寸纳米结构和超细结构块体金属材料的有效应用。本项目将在对粉末颗粒界面在粉末固结过程中向晶界和相界转变的初步理解和认识的基础上对每类颗粒界面转化机理以及四大关键因素（温度，压力，粉末颗粒变形度和氧化膜的特性和厚度）对转化速度的影响进行系统深入地研究，并建立和验证颗粒界面转化动力学模型。研究将采用新的实验方法表征固结块内未转化颗粒界面。在前期研究的基础上，本项目将制备出不含未转化颗粒界面和颗粒界面孔洞的纳米结构，超细结构，和纳米-超细-微米混合结构块体铝，镍，铜及其合金样品，并研究结构尺寸对其拉伸机械性能和抗冲击性能的影响。

中文关键词： 热机械粉末固结；颗粒界面转化；纳米结构金属材料；颗粒界面强度；力学性能

英文摘要： The untransformed interparticle boundaries and interparticle boundary cavities have singificant detrimental effects on the mechanical and physical properties of the bulk nanostructured (NS) and ultrafine structured (UFS) metallic materials synthesised by powder consolidation, and therefore prevent demonstration of the true and potentially outstanding properties of such materials.It is still very difficult to accurately determine the powder consolidation techniques and conditions which not only allow the complete transoformation of interparticle boundaries in the powder compact but also strictly limit the growth of grains during powder consolidation. Based on the preliminary understanding and knowledge on the transformation of interparticle boundaries into grain boundaries and interphase interfaces,this project will undertake a systematic and in-depth study on the mechanism of the transoformation of each type of the interparticle boundaries, the effects of four key factors (temperature, pressure, the level of powder particle deformation, and the property and thickness of powder particle surface oxide layers) on the rate of the tranformation of interparticle boundaries. The research will also establish and validate the kinetic model of the transformation of the interparticle boundaries. The research will utilise a

英文关键词： thermomechanical powder consolidation；transformation of interparticle boundaries；nanostructured metallic materials；stength of interparticle boundaries；mechanical properties