【作者】 魏伟；

【导师】 史庆南；

【作者基本信息】 昆明理工大学 ， 2002， 硕士

【摘要】 论文首次提出一种新型金属载体的低成本成形方法，即“多芯线粉末挤压法”，并用此方法进行了金属载体成形的相关研究。主要开展了以下三个方面的基础研究工作：①金属载体材料的选择与设计；②多芯线粉末挤压成形技术的工艺流程、模具设计、粉末挤压力学参数的实验研究和理论分析；③初步探讨了粉末体挤压成形过程的有限元数值模拟理论。 实验重点研究了纯Al、Al-Fe的粉末挤压，并对粉末的挤压变形行为进行了理论分析，提出了与通常挤压变形过程的截然不同的三个阶段，基本工艺流程为混粉→保湿→预压→挤压→烧结→后处理。 试样断面形貌分析，XRD，密度和线膨胀系数的研究，初步证明了多孔金属载体材料设计的正确性，及金属载体所具有的一些优异性能。在数值模拟理论中，推导了粉末体变形的应力-应变关系等效应变速率方程和求解的整体矩阵方程 因此，“多芯线粉末挤压成形工艺及其数值模拟理论研究”验证了多芯线粉末挤压成形在工艺上的可行性，是金属载体成形的较好方法。实验研究所获得的基础数据和理论分析，为“多芯线粉末挤压”的进一步研究奠定了基础。更多还原

【Abstract】 A new forming method, which is Multi-Core-Line-Die Powder Extrusion (MCLDPE), of low cost metallic carrier is firstly presented in this paper. Correlative research on metallic carrier forming is investigated by this method. There are three aspects foundation pursuits, comprising ?To select and design metallic carrier materials (2) Technique flow , die designation and mechanic parameters of Multi-Core-Line-Die Powder Extrusion Forming and (3) To probe into finite element method (FEM) mathematical simulation theory of powder-compact extrusion forming.Powder extrusion of pure Aluminum and Aluminum-Iron powder is detailedly studied. Extruded powder deformation behavior is theoretically analyzed. Three periods in powder extrusion are different from routine extrusion. Rudimental technique flow comprises blended powder → keeping humidity → previous press → sinter → disposal. Metallography, XRD, density and heat expand parameter are also investigated at length. Correctness of materials designation of porous metallic carrier, predominant performances of metallic carrier are elementarily proved.In mathematical simulation theory, stress-strain relation of powder-compactdeformation , equivalent strain velocity equation , and unitary matrix equation ,are deduced.Therefore, feasibility of Multi-Core-Line-Die Powder Extrusion Forming is validated by Research on Mathematical Simulation Theory and Powder Extrusion Forming Technology of Multi-Core-Line-Die, which is a better forming method of metallic carrier. Basal experimental data and theory analysis are foundations for further research on Multi-Core -Line-Die Powder Extrusion Forming.更多还原