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1.
作为超高温材料使用的梯度功能材料作为以难熔金属及其化合物为主要成分的梯度功能材料,要求具有综合的功能和梯度变化的构造。实现以下目的:(1)缓和热应力。在不互溶的金属-金属系混合物中,W/Cu系梯度功能材料受到最广泛的关注,类似的材料还有Mo/Cu系。...  相似文献   

2.
掺杂WC/Co的Al2O3/TiC/Ni系梯度功能材料研究了添加WC/Co的Al2O3-WC-Co/TiC/Ni系梯度功能材料(FGM)的力学性能,该材料是以Al2O3/TiC/Ni系为基体,在表面层Al2O3中添加WC-Co系组分制成的对称型FGM...  相似文献   

3.
W-Cu梯度功能复合材料制备梯度功能材料,可以采用物理气相沉沉化学气相沉积、热喷涂、烧结和自蔓延高温合成等工艺。自蔓延高温合成方法只能应用在发生燃烧反应的情况下Z而物理和化学气相沉积与热喷涂基本上都是涂复过程,只能用于生产薄膜梯度功能材料;烧结法可生...  相似文献   

4.
W-Cu电子封装材料的气密性   总被引:28,自引:3,他引:25  
分析了传统熔渗法生产的WCu材料气密性差的工艺因素,采用加入一定数量的诱导铜的工艺方法进行压型,通过调整成型压力,使生坯中的W含量达到电子封装WCu15含钨量的标准,其余的Cu在熔渗时渗入。实验表明,加入1%~2.5%的诱导铜的生坯在1350℃熔渗1.5h,其气密性可以达到满意的效果。  相似文献   

5.
研究了金属Nb液态渗Cu制备复合材料的方法,并通过对Nb/20Cu复合材料的组织分析和性能研究,确认Nb/20Cu复合材料比纯铌粉末冶金材料的力学,电学,热学和抗氧化性能均具有所提高,从而为改善钝铌制品的使用性能提供了试验依据。rmhj tlf  相似文献   

6.
CuCr25W1Col合金的性能研究   总被引:10,自引:4,他引:6  
为节约Cr资源,提高CuCr触头材料的耐电击穿性能并满足其大规模生产的需要,根据W、Co的选择相强化作用,以钝Cu、Cr块为原料,采用Ar气保护熔炼法制备CuCr25W1Col头合金,并对其性能进行研究。实验结果表明,该合金晶粒尺寸细小,含气量低,耐电压强度已达到常规头材料的水平。  相似文献   

7.
采用冷等静压(CIP)成型-烧结-熔渗-热等静压(HIP)处理工艺制取高密度、高性能电火花加工用WCu电极材料。使WCu电极性能有较大幅度的提高。  相似文献   

8.
采用冷等静压(CIP)成型─—烧结─—熔渗─—热等静压(HIP)处理工艺制取高密度、高性能电火花加工用WCu电极材料。使WCu电极性能有较大幅度的提高。  相似文献   

9.
Cu50Cr50触头材料的性能   总被引:5,自引:1,他引:4  
采用松装熔渗方法制备Cu50Cr50真空断路器用触头材料,研究了电解Cr粉粒度,粉末的含氧量和含氮量及添加Ni粉末对Cu50Cr50触头材料性能的影响,结果表明,使用粒度为75μm~150μm的预处理电解铬粉末和无氧铜块,在干燥的氢气气氛中,于1200℃进行30min熔渗,可获得含氧量为0.03%,含氮量(0.003~0.006)%,(质量)密度(7.8~7.9)g/cm^3,电导率(1.50~1  相似文献   

10.
新型Cu/Pd和合电触点材料   总被引:1,自引:1,他引:0  
卢峰 《贵金属》2000,21(3):1-7
研究制备Cu/Pd25、Cu/Pd30、Cu/Pd40和Cu/Pd60(wt%)复合材料并测量它们的力学及电学性能,利用金相显微镜和扫描电镜观察了复合 组织结构,对不同Pd含量的Cu/Pd复合材料的性能进行比较。这类新型Cu/Pd复合材料显示出优异的可加工性、适中的硬度和非常高的电导率,是目前世界上最好的直流触点材料之一。  相似文献   

11.
超高压梯度烧结法制备W/Cu功能梯度材料   总被引:15,自引:2,他引:13  
提出了一种制备具有递变电阻及高熔点差功能梯度材料的新方法-超高压梯度烧结法,并成功制备出了相对密度达到96%的W/Cu梯度功能材料。推导了通电烧结过程中梯度材料内部的温度分布,表明温度场与电流密度及材料的厚度大致成平方的梯度分布模式;考察了不同的烧结助剂对W/Cu梯度材料致密化的影响,发现Ni比V和Zr有更好的致密化效果;观察了W/Cu梯度材料显微结构并对梯度烧结的过程机理进行了初步探讨。  相似文献   

12.
Copper matrix composites have received more attentions as possible candidate for thermal and electrical conductive materials to be used in electrical contact applications. In this study, five-layered Cu/YSZ(yttria-stabilized zirconia) functionally graded material(FGM) and copper matrix composite specimens containing 3 and 5 vol% YSZ particles plus pure Cu specimen were synthesized using powder metallurgy(PM) route and spark plasma sintering(SPS)consolidation process. The microstructural and some physical, mechanical features of all specimens were characterized.Microscopic examinations showed that ultrafine YSZ particles were distributed in the copper matrix almost homogeneously. An appropriate interface was observed at each layer of FGM. The density measurement indicated that the graded structure of the composite could be well densified after the SPS process. The microhardness values of various layers of Cu/YSZ FGM specimen were gradually altered from 56.3(pure copper side) to 75.2 HV(Cu-5 vol% YSZ side). The increase of YSZ content resulted in a decrease in electrical conductivity. Additionally, thermal conductivity of Cu/YSZ FGM specimen [308.0 W/(m K)] was determined to be higher than that of the Cu-5 vol% YSZ composite specimen [260.7 W/(m K)]. Accordingly, it can be concluded that the Cu/YSZ FGM can be a good candidate for the electrical applications, like sliding electrical contacts, where different material characteristics in the same component are required.  相似文献   

13.
运用ANSYS12.0软件对W/Cu梯度材料进行热应力模拟分析,并对结构进行优化设计。结果表明,随着成分分布指数(p)的增加,最大热应力先减小后增大;在p=1.3,热流密度为30 MW/m2时,最大热应力值最小为180 MPa,与非梯度材料相比最大等效热应力降低79%;最优化的梯度层厚度大于3 mm,梯度层数4~6层,钨板的厚度1~3 mm。  相似文献   

14.
W/Cu功能梯度材料性能优异应用广泛,以W/Cu功能梯度材料的制备方法为研究对象,探讨不同制备方法存在的优缺点,包括熔渗法、粉末冶金法及等离子喷涂法。作为等离子体材料应与等离子体相适应,耐热冲蚀。在电子领域中,其一侧应满足与基板的封接问题,另一侧满足高导热、低热膨胀系数的要求。目前虽然研发出多种新工艺、新技术,但需进一步了解其控制因素及影响机理,另外每种工艺适用范围比较小,需开发高效、低成本、适用广、易控制的制造工艺。  相似文献   

15.
采用有限元ANSYS软件对偏滤器第一壁W/Cu FGM进行热应力模拟分析,并对其参数进行优化设计。结果表明,优化后的梯度层应力较无梯度层时得到了极大的缓和,最大等效应力值降低58%。最优化的梯度层层数为5,Cu浓度分布指数为0.4;同时在10 MW/m2的表面热流冲击下,表现出较好的抗热冲击能力  相似文献   

16.
Three-layered (W–25Cu/W–50Cu/W–75Cu, volume fraction) W/Cu functionally graded material (FGM) was synthesized by spark plasma sintering (SPS) at different temperatures for 5 min under a load of 40 MPa. The influences of different sintering processes on relative density, hardness, thermal conductivity and microstructure at various layers of sintered samples were investigated. The experimental results indicated that the graded structure of the composite could be well densified after the SPS process. The relative density increased with the increment of sintering temperature and it was up to 96.53% as sintered at 1050 °C. In addition, the thermal conductivity reached 140 W/m·K at room temperature and 151 W/m·K at 800 °C, which could be ascribed to the specific structure that W particles enwrapped by net-like Cu. And the Vickers hardness was converted from 4.11 to 4.68 GPa.  相似文献   

17.
用化学镀法和粉末冶金的方法制备高致密的W/Cu梯度热沉材料。用场发射扫描电镜观察了材料的组织结构、界面和断口形貌。对材料的机械性能也进行了表征,如抗弯强度和显微硬度。结果表明材料每一层都很致密且组织结构均匀。从截面上材料成分呈梯度分布,每层之间没有明显的界面。三层W/Cu梯度热沉材料的相对密度可达99.2%。散热层、过渡层和封接层的显微硬度值分别是200、210和240 HV。抗弯实验结果所示封接层和散热层作为承重抗弯表面时的抗弯强度分别是428.5MPa和480.7MPa。  相似文献   

18.
目的 研究W/ODS铁素体钢功能梯度材料(W/ODS FGM)服役条件下的热应力,期望获得较合理的W/ODS FGM材料设计,以达到热应力优化的效果。方法 采用有限元分析方法,结合偏滤器的服役条件,通过改变W/ODS FGM材料梯度层成分分布指数p、梯度层厚度HFGM以及金属W涂层厚度HW,探索各参量的变化对热应力大小及分布的影响。结果 梯度层成分分布指数p值增大,梯度层的应力值会随之增大,而W层的热应力先减小后增大。当p=0.5时,最大热应力出现在梯度层的中段;当p=1、2时,最大应力由FGM层中段转移至FGM/W层的交界处。梯度层厚度HFGM增大,涂层的热应力会大幅提高。梯度层厚度较厚或较薄都会导致热应力在FGM/W交界处集中。W涂层厚度HW增大,会导致W/FGM界面的热应力增大,增添了涂层自身的不稳定性。结论 梯度层成分分布指数和厚度的增大均会引起涂层热应力的增大,并导致最大热应力区的转移。W涂层的增厚会使结构的热应力增大,且最大应力值位于W/FGM界面,不利于涂层寿命的提高。HW=HODS=1 mm、HFGM=8 mm、p=0.5和HW=HODS=1 mm、HFGM=4 mm、p=1的最大热应力区位于梯度层中段,且后者的最大应力值小于前者,故HW=HODS=1 mm、HFGM=4 mm、p=1的结构较优。  相似文献   

19.
The spray-deposited SiCp/Al-20Si-3Cu functionally graded material (FGM) can meet the structure design requirements of brake disk. The effects of rotational speed and load on the wear and friction behaviors of the SiCp/Al-20Si-3Cu FGM sliding against the resin matrix friction material were investigated. For comparison, the wear and friction behaviors of a commercially used cast iron (HT250) brake rotor were also studied. The results indicate that the friction coefficient of the SiCp/Al-20Si-3Cu FGM decreases constantly with the increase of load or rotational speed and is affected by the gradient distribution of SiC particles. The wear rate of the SiCp/Al-20Si-3Cu FGM firstly increases, then decreases and finally increases again with increasing load or speed, and is about 1/10 of that of HT250. Based on observations and analyses on the morphology and substructure of the worn surface, the mechanical mixing layer acts as a protective coating and lubricant, and its thickness reduces with the SiC content increasing. Furthermore, it is proposed that the dominant wear mechanism of SiCp/Al-20Si-3Cu FGM changes from the abrasive wear to the oxidative wear and further to the delamination wear with increasing load or speed.  相似文献   

20.
A new technology of functionally graded materials(FGM) mould fabricated by plasma spraying and arc spraying was developed. According to applied characteristic of plastic mould, the reasonable coatings of FGM were designed and their microstructures were analyzed. At the same time, some key problems were solved including spray mould fabricating, FGM forming and demoulding, etc. The results show that the service performance of the FGM mould is much more excellent than the one composed of the traditional materials, and the life span can also be greatly increased. The technology will have a significant influence on materials development in mould industry.  相似文献   

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