【作者】 李波；

【导师】 王清周；

【作者基本信息】 河北工业大学 ， 材料学， 2017， 硕士

【摘要】 为开发综合性能优异的新型高阻尼材料以满足社会诸多领域减震降噪的迫切需求,本文以NaCl为造孔剂采用烧结-脱溶工艺对多孔NiTi及多孔NiTiCu形状记忆合金进行了制备,同时采用无压熔渗技术向多孔NiTiCu形状记忆合金中填充了金属Mg,从而制得了一种高阻尼低密度的Mg/NiTiCu基复合材料。本文分别采用SEM、XRD、DSC、DMA以及万能材料试验机对所得材料的宏、微观形貌、物相组成、相变行为、阻尼以及压缩吸能特性进行了表征与测试。研究发现,经过工艺优化以后,采用烧结-脱溶技术可以成功制得孔隙率、孔径可控、孔洞形貌规则且分布均匀、同时具有通孔结构的多孔NiTi、NiTiCu形状记忆合金,从而有效解决了当前对此类材料制备工艺中的不足。本文所制得多孔NiTi、NiTiCu形状记忆合金均具有优良的阻尼性能以及压缩吸能特性,同时,因以Cu代Ni,后者较之前者具有更为稳定的马氏体转变性能。通过无压熔渗技术所制得的Mg/NiTiCu复合材料较之多孔NiTiCu形状记忆合金具有显著提高的压缩强度、压缩吸能本领以及阻尼性能。这可归结为Mg/NiTiCu复合材料力学性能的复合效应以及其多重阻尼源叠加的效应。因此,Mg/NiTiCu复合材料是一类功能-结构一体化的新型的高阻尼材料,该材料的成功制备可以为新一代高阻尼材料的设计与开发提供思路。更多还原

【Abstract】 To develop high damping materials with excellent comprehensive properties to meet the urgent needs of vibration and noise reduction in many areas of society.In this paper,porous NiTi and porous NiTiCu shape memory alloys(SMAs)were prepared by using NaCl as space-holders via sintering dissolution process.In addition,a Mg/NiTiCu composite with high damping and low density was also prepared by filling Mg into the pores of porous NiTiCu SMA via pressureless infiltration technique.In this paper,SEM,XRD,DSC,DMA and universal material testing machine were used to characterize and test the macro and micro morphologies,phase composition,phase change behavior,damping and energy absorption properties of the materials.It was found that,after optimizing the process,the porous NiTi and porous NiTiCu SMAs with controllable pore size and porosity,as well as regular and uniformly distributed open pores could be successfully prepared.Deficiencies in the preparation of such materials was therefore resolved.The porous NiTi and NiTiCu SMAs prepared in the present study possess excellent damping and compression energy absorption properties.At the same time,due to the replacement of Ni by Cu,the latter has more stable martensitic transformation properties than the former.Co MPared with the porous NiTiCu SMA,the Mg/NiTiCu composites prepared by pressureless infiltration technique possess significantly improved compressive strength,compressive energy absorption and damping properties.This can be attributed to the composite effect of the mechanical properties and the superposition of multiple damping sources of Mg/NiTiCu composites.Therefore,the Mg/NiTiCu composite is a new kind of high damping material with the integration of function and structure.The successful preparation of this material can provide a new idea for the design and development of the new generation of high damping materials.更多还原