放电等离子法制备Cu-Zr-AIN复合材料及其性能的研究
发布时间：2018-09-02 07:11
【摘要】：颗粒增强铜基复合材料在保持良好导电、导热性的前提下,能够提高复合材料的强度、硬度等性能。颗粒增强相的种类有很多,而AlN具有高熔点、高硬度、热膨胀系数小等特点,使得AlN增强铜基复合材料受到越来越多的人关注。本研究将Cu、Zr、AlN粉末按一定的比例称取,通过行星式球磨机将粉末进行混合,对所制备的复合粉末进行XRD物相分析、SEM表面组织观察以及粒度分析,研究不同球磨时间的Cu-Zr-AIN复合粉末性能。采用放电等离子烧结技术得到Cu-Zr-AIN复合材料,采用金相光学显微镜、扫描电子显微镜(SEM)和能谱仪(EDS)等对复合材料的微观组织进行观察分析,并探究了烧结温度、AlN含量对Cu-Zr-AIN复合材料的致密度、抗压强度、硬度、导电性以及摩擦磨损性能的影响。随着球磨时间的延长,复合粉末的Cu、Zr的衍射峰强度降低,衍射峰不断宽化,晶粒得到不断细化。Cu-Zr-AIN复合粉末在球磨过程中,一部分Zr固溶到Cu中,形成铜锆过饱和固溶体；球磨到20h后,出现新相Cu8Zr3,延长球磨时间,金属间化合物衍射峰增强,新产生的金属间化合物增多。AlN的衍射峰一直存在并且其衍射峰的强度变化不大,说明随着球磨的进行,AlN与Cu粉末混合的更加均匀,但并未发生分解。在球磨过程中,球磨30h后,平均体积粒径可达4.956um,继续延长球磨时间复合粉末的粒度开始有所增加,粉末团聚加重。通过实验分析,得出该复合粉末的最佳球磨时间为30小时。经过放电等离子烧结得到的Cu-Zr-AIN复合材料,随着烧结温度的增加,Cu-Zr-AIN复合材料的致密度逐渐增加。烧结温度在800℃时,复合材料的微观组织均匀,烧结温度高于800℃后,复合材料晶粒粗化,致密度增加缓慢。其显微硬度和抗压强度,在烧结温度700℃到800℃范围内,随着烧结温度的升高逐渐提高,烧结温度升高到800℃以后,复合材料的显微硬度和抗压强度呈现下降趋势。选取800℃为最佳烧结温度。经过放电等离子烧结所得到的复合材料,随着AlN含量的增加,所得复合材料的密度、致密度和导电性能都不断降低。而显微硬度和抗压强度都呈现出先增大后变小的变化趋势。随着AlN含量的增加,复合材料的摩擦系数先变小,然后增大。当AlN含量为5%时,摩擦系数出现明显降低。当AlN含量超过5%后,复合材料摩擦系数逐渐增大。随着AlN含量的增加,犁沟由深变浅,剥落的片状组织减少,复合材料的磨损面变得平整,能够延缓严重磨损的出现。本研究的意义在于探索放电等离子法制备Cu-Zr-AIN复合材料的工艺,以达到制备高强高导铜基复合材料的目的。
[Abstract]:Particle reinforced copper matrix composites can improve the strength and hardness of the composites under the premise of good conductivity and thermal conductivity. There are many kinds of particle reinforced phases, while AlN has the characteristics of high melting point, high hardness and low coefficient of thermal expansion, which makes AlN reinforced copper matrix composites attract more and more attention. In this study, the Cu,Zr,AlN powder was weighed according to a certain proportion, and the powder was mixed by a planetary ball mill. The surface microstructure and particle size of the prepared composite powder were analyzed by XRD. The properties of Cu-Zr-AIN composite powder with different milling time were studied. Cu-Zr-AIN composites were obtained by spark plasma sintering (SPS). The microstructure of the composites was observed and analyzed by optical microscope, scanning electron microscope (SEM) and energy spectrometer (EDS). The effects of sintering temperature and AlN content on the density, compressive strength, hardness, electrical conductivity and friction and wear properties of Cu-Zr-AIN composites were investigated. With the prolongation of milling time, the diffraction peak intensity of Cu,Zr decreases, the diffraction peak broadens, and the grain size of Cu-Zr-AIN composite powder is continuously refined. During ball milling, part of Zr is dissolved in Cu, forming copper-zirconium supersaturated solid solution. After ball milling for 20 h, the new phase Cu8Zr3, prolonged the milling time, the diffraction peak of intermetallic compound increased, and the diffraction peak of the newly produced intermetallic compound increased, and the intensity of the diffraction peak changed little. The results show that the mixture of AlN and Cu powder is more uniform with ball milling, but it does not decompose. During the milling process, after 30 hours of ball milling, the average volume particle size can reach 4.956 um.And the particle size of the composite powder increased and the agglomeration of the powder increased with the further prolongation of the milling time. Through experimental analysis, the optimum milling time of the composite powder is 30 hours. The density of Cu-Zr-AIN composites increased with the increase of sintering temperature. When the sintering temperature is 800 鈩，
本文编号：2218641
[Abstract]:Particle reinforced copper matrix composites can improve the strength and hardness of the composites under the premise of good conductivity and thermal conductivity. There are many kinds of particle reinforced phases, while AlN has the characteristics of high melting point, high hardness and low coefficient of thermal expansion, which makes AlN reinforced copper matrix composites attract more and more attention. In this study, the Cu,Zr,AlN powder was weighed according to a certain proportion, and the powder was mixed by a planetary ball mill. The surface microstructure and particle size of the prepared composite powder were analyzed by XRD. The properties of Cu-Zr-AIN composite powder with different milling time were studied. Cu-Zr-AIN composites were obtained by spark plasma sintering (SPS). The microstructure of the composites was observed and analyzed by optical microscope, scanning electron microscope (SEM) and energy spectrometer (EDS). The effects of sintering temperature and AlN content on the density, compressive strength, hardness, electrical conductivity and friction and wear properties of Cu-Zr-AIN composites were investigated. With the prolongation of milling time, the diffraction peak intensity of Cu,Zr decreases, the diffraction peak broadens, and the grain size of Cu-Zr-AIN composite powder is continuously refined. During ball milling, part of Zr is dissolved in Cu, forming copper-zirconium supersaturated solid solution. After ball milling for 20 h, the new phase Cu8Zr3, prolonged the milling time, the diffraction peak of intermetallic compound increased, and the diffraction peak of the newly produced intermetallic compound increased, and the intensity of the diffraction peak changed little. The results show that the mixture of AlN and Cu powder is more uniform with ball milling, but it does not decompose. During the milling process, after 30 hours of ball milling, the average volume particle size can reach 4.956 um.And the particle size of the composite powder increased and the agglomeration of the powder increased with the further prolongation of the milling time. Through experimental analysis, the optimum milling time of the composite powder is 30 hours. The density of Cu-Zr-AIN composites increased with the increase of sintering temperature. When the sintering temperature is 800 鈩，
本文编号：2218641
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